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2 مرفق
السلام عليكم
دا مرجع كيمياء عضويه لطلبه كليه االعلوم جميع التخصصات ان شاء تستفيدوا بيه كتير جدا وهو لكل الاقسام احتفظ به وادعي لي وان شاء الله نكمل الباقي اسمه ( سولومون ) |
ربنا يجازيك كل خير بجد :)
احنا باذن الله عندنا كيميا غير عضوية تيرم اول و كيميا عضوية تيرم تانى انا قرأت النصائح الاولى اللى فى التحميل الاول وهى فعلا جميلة ربنا يجعله فى ميزان حسناتك :) |
شكرااا جدااا يا استاذ عاطف على المرجع
وفى انتظار باقى المراجع وجزاك الله خيرا |
ربنا يخليك يا رب يا مستر
مرسى |
جزاك الله كل خير أستاذ عاطف
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شكرا ليك يااستاذ عاطف....وياريت لو عند حضرتك حل لكيفيه مذاكره ال thermochemistry ...ياريت تقولي عليه...لاني بجد بكره الفرع ده فوق مانت متخيل..
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مشكور جدا يا استاذ عاطف
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شكراااااااااا جدا ياستاذ عاطف
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جزاك الله كل خير يااستاذ عاطف
وربنا يجعله فى ميزان حسنات حضرتك ومستنيين باقى المراجع فى امان الله |
متشكرين منك أوى يا أستاذ عاطف
وربنا يجعله فى ميزان حسناتك |
كيمياء أولي علوم....
Chemical Bonding
Chemical compounds are formed by the joining of two or more atoms. A stable compound occurs when the total energy of the combination has lower energy than the separated atoms. The bound state implies a net attractive force between the atoms ... a chemical bond. The two extreme cases of chemical bonds are: Covalent bond: bond in which one or more pairs of electrons are shared by two atoms. Ionic bond: bond in which one or more electrons from one atom are removed and attached to another atom, resulting in positive and negative ions which attract each other. Other types of bonds include metallic bonds and hydrogen bonding. The attractive forces between molecules in a liquid can be characterized as van der Waals bonds. http://hyperphysics.phy-astr.gsu.edu...l/naclpott.gif Sodium chloride Ionichttp://hyperphysics.phy-astr.gsu.edu...mol/h2molt.gif Covalent Bonds Covalent chemical bonds involve the sharing of a pair of valence electrons by two atoms, in contrast to the transfer of electrons in ionic bonds. Such bonds lead to stable molecules if they share electrons in such a way as to create a noble gas configuration for each atom. Hydrogen gas forms the simplest covalent bond in the diatomic hydrogen molecule. The halogens such as chlorine also exist as diatomic gases by forming covalent bonds. The nitrogen and oxygen which makes up the bulk of the atmosphere also exhibits covalent bonding in forming diatomic molecules. http://hyperphysics.phy-astr.gsu.edu...lewisbond2.gif Covalent bonding can be visualized with the aid of Lewis diagrams. Polar Covalent Bonds Covalent bonds in which the sharing of the electron pair is unequal, with the electrons spending more time around the more nonmetallic atom, are called polar covalent bonds. In such a bond there is a charge separation with one atom being slightly more positive and the other more negative, i.e., the bond will produce a dipole moment. The ability of an atom to attract electrons in the presense of another atom is a measurable property called electronegativity Ionic Bonds In chemical bonds, atoms can either transfer or share their valence electrons. In the extreme case where one or more atoms lose electrons and other atoms gain them in order to produce a noble gas electron configuration, the bond is called an ionic bond. Typical of ionic bonds are those in the alkali halides such as sodium chloride, NaCl. http://hyperphysics.phy-astr.gsu.edu.../lewisbond.gif Ionic bonding can be visualized with the aid of Lewis diagrams Metallic Bonds The properties of metals suggest that their atoms possess strong bonds, yet the ease of conduction of heat and electricity suggest that electrons can move freely in all directions in a metal. The general observations give rise to a picture of "positive ions in a sea of electrons" to describe metallic bonding. Hydrogen Bonding Hydrogen bonding differs from other uses of the word "bond" since it is a force of attraction between a hydrogen atom in one molecule and a small atom of high electronegativity in another molecule. That is, it is an intermolecular force, not an intramolecular force as in the common use of the word bond. When hydrogen atoms are joined in a polar covalent bondwith a small atom of high electronegativity such as O, F or N, the partial positive charge on the hydrogen is highly concentrated because of its small size. If the hydrogen is close to another oxygen, fluorine or nitrogen in another molecule, then there is a force of attraction termed a dipole-dipole interaction. This attraction or "hydrogen bond" can have about 5% to 10% of the strength of a covalent bond. Hydrogen bonding has a very important effect on the properties of water and ice. Hydrogen bonding is also very important in proteins and nucleic acids and therefore in life processes. The "unzipping" of DNA is a breaking of hydrogen bonds which help hold the two strands of the double helix together. ------------------- Chemical Bonds Because of the tendency of atoms to complete their outer energy shells with the stable number of electrons for each shell, atoms with incomplete shells have a tendency to gain electrons, lose electrons or share electrons. Atoms that have gained or lost electrons become ions. Oppositely charged ions form ionic bonds. Atoms that share electrons form covalent bonds. A much weaker, but very important bond in biological systems is the hydrogen bond. Ionic bondsThe following animation shows how ions of sodium and chlorine are formed. The outer shell of sodium contains one electron. If it can lose that electron it will have a stable outer shell with 8 electrons (2-8) and become an ion with a positive charge. The positive charge (+1) is due to the presence of 10 electrons and 11 protons in the sodium ion. Chlorine has 17 electrons in its outer shell and will be stable if it can gain an electron. The result will give chlorine 18 electrons (2-8-8) and convert the chlorine atom into an ion with a negative charge (18 electrons and 17 protons) called chloride. Play the animation to see how these two ions form. The moving red dot is an electron which moves from the sodium atom to the chlorine atom. Notice that at the end of the animation, the outer shell of each ion is now filled. Sodium now has 2 shells and chlorine has three. http://www2.nl.edu/jste/nacl.gifThe oppositely charged ions in the animation will be attracted to each other and form an ionic bond. Ionic bonds are weak bonds. It does not take much energy to make them and they can be easily broken. When sodium (Na+) ions bond with chloride (Cl-) ions they form common table salt, sodium chloride (NaCl). © The Biology Project, used with permission Covalent bonds Atoms can fill their outer shells by sharing electrons. When they do this, they form covalent bonds. It takes much energy to make a covalent bond and much energy is released when they are broken. This makes covalent bonds very strong bonds. In the animation, two hydrogen atoms share each other's electrons and form a molecule of hydrogen. The animation fails to show this, but the two electrons are actually zooming around both nuclei so fast that it is as if each hydrogen atom has 2 electrons in its outer shell. This sharing provides each atom with the required 2 electrons to fill its first shell. We can indicate this covalent bonding by writing H-H. The line connecting the two letters represents the bond. Sometimes each atom shares two electrons with its partner (a total of 4 electrons) and a double bond is formed. This is written C=C or O=O. Similarly, when each partner shares 3 of its electrons with the other, a triple bond forms. Covalent bonds can be nonpolar, or polar. Be sure to click here to learn the difference between polar and nonpolar bonds.Hydrogen bonds Polar molecules can be attracted to each other much as oppositely charged ions are.http://www2.nl.edu/jste/water.gif The attraction will, however, be much weaker since polarity results in only a partial charge. The weak attraction between the slightly positive hydrogen region of one polar covalent bond (usually the hydrogen is bonded to oxygen or nitrogen) and the negative region of another polar covalently bonded molecule is called a hydrogen bond. Water molecules have such polarity (see polar). The diagram shows how water molecules are linked together by hydrogen bonds. You can think of water molecules as tiny magnets with opposite poles, much like the poles of a magnet. Opposite poles attract each other. Water molecules are stuck to each other by this attracting force. مع الشكر وللكلام بقيه يتبعHydrogen bonds are weaker than ionic bonds and much weaker than covalent bonds. Nevertheless, they are essential in biological systems. Many weak bonds working together can result in a very strong connection. The situation is similar to a strip of Velcro where many tiny and weak links form a remarkably stable attachment. Many of the characteristics of proteins and nucleic acids (DNA and RNA) are due to hydrogen bonding, as are very important properties of water. د عاطف خليفه |
روعه يامستر عاطف....ياريت حضرتك لو عندك كيمياء عامه سنه أولي تنزلها....واللي انت منزله ده أول درس فيها....وبجد جامده جدا....بس لو نزلت في ملف وورد هتبقي افضل....وياريت متحرمناش في القسم ده من مواضيعك الجامده والمفيده بأستمرار......
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5 مرفق
ودا مرجع في الروابط روعه الروابط كلها
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1 مرفق
وده باقي الروابط المرجع ودعواتكم
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طيب تسمحلي اثبت الموضوع وتضيف عليه بقيت الكيمياء لأولي....لأن دي فعلا الدروس المقرره والثابته في الكيمياء...بس هغير اسم الموضوع بعد اذنك اخليه كيمياء أولي .....وان شاء الله هساعد حضرتك في اضافات للموضوع
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تحت امرك اخي الحبيب
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معلش يامستر ...عارف اني طماع:d...بس الموضوع فعلا جامد جدا ومفيد لطلبه أولي علوم....
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الكيمياء العامه الدرس للاول القياسات -------------------------- absolute error. absolute uncertainty. Compare with relative errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The uncertainty in a measurement, expressed with appropriate units. For example, if three replicate weights for an object are 1.00 g, 1.05 g, and 0.95 g, the absolute error can be expressed as ± 0.05 g. Absolute error is also used to express inaccuracies; for example, if the "true value" is 1.11 g and the measured value is 1.00 g, the absolute error could be written as 1.00 g - 1.11 g = -0.11 g. Note that when absolute errors are associated with indeterminate errorshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, they are preceded with "±"; when they are associated with determinate errorshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, they are preceded by their sign. absolute temperature. Temperature measured on a scale that sets absolute zerohttp://antoine.frostburg.edu/chem/se...s/asterisk.gif as zero. In the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system, the kelvinhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif scale is used to measure absolute temperature. absolute zero. ) The temperature at which the volume of an ideal gashttp://antoine.frostburg.edu/chem/se...s/asterisk.gif becomes zero; a theoretical coldest temperature that can be approached but never reached. Absolute zero is zero on the Kelvin scale, -273.15°C on the Celsiushttp://antoine.frostburg.edu/chem/se...s/asterisk.gif scale, and -459.67°F on the Fahrenheit scale. accuracy. Compare with precisionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and truenesshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Accuracy is the correctness of a single measurement. The accuracy of a measurement is assessed by comparing the measurement with the true or accepted value, based on evidence independent of the measurement. The closeness of an average to a true value is referred to as "trueness". ampere. (A) amp. The SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif unit of electric currenthttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, equal to flow of 1 coulombhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of charge per second. An ampere is the amount of current necessary to produce a force of 0.2 micronewtons per meter between two arbitrarily long, arbitrarily thin wires, placed parallel in a vacuum and exactly 1 m apart. Named for 19th century physicist André Marie Ampère. Angstrom. (Å) Ångstrom; Ångstrom units. A non-SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif unit of length used to express wavelengths of light, bond lengths, and molecular sizes. 1 Å = 10-10 m = 10-8 cm. atto-. (a) Prefix used in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system meaning "multiply by 10-18". For example, 3 am means 3× 10-18 meters. base unit. Base units are unitshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif that are fundamental building blocks in a system of measurement. There are seven base units in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system. calibration. Calibration is correcting a measuring instrument by measuring values whose true values are known. Calibration minimizes systematic errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Celsius. (°C) Celsius temperature scale; Celsius scale. A common but non-SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif unit of temperature, defined by assigning temperatures of 0°C and 100°C to the freezing and boiling points of water, respectively. centi-. (c) Prefix used in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system meaning "one hundredth of". For example 1 cm means "one hundredth of a meter"; 2.3 cg could also be written "2.3 × 10-2 g" or "0.023 g". cgs. Compare with SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. An older metric system of units that uses centimeters, grams, and seconds as base units. conversion factor. (10 in) 2.54 cmA conversion factor is a fraction that relates one unit to another. Multiplying a measurement by a conversion factor changes the units of the measurement. For example, since 1 in = 2.54 cm, to convert 10 inches to centimeters, 1 in= 25.4 cm coulomb. (C) The SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif unit of electric charge, equal to the amount of charge delivered by a current of 1 amperehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif running for 1 second. One mole of electrons has a charge of about 96487 C. density. (http://antoine.frostburg.edu/chem/senese/images/rho.gif,d) Compare with specific gravityhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Mass of a substance per unit volume. Saying "the density of mercury is 13.55 g/cm3 " is the same as saying "the mass of exactly 1 cm3 of mercury is 13.55 g". derived unit. Derived units are unitshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif constructed from the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system's base unitshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. For example, the SI unit for density is kg/m3, derived from the base units kg and m. dyne. (dyn) The unit of force in the obsolete cgshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system of units. A dyne is the force required to accelerate a 1 g mass by 1 cm/s per second. femto-. (f) Prefix used in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system meaning "multiply by 10-15". For example 22 fg means 22× 10-15 g. gram. A metric unit of mass, equal to 1/1000 of a kilogramhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Kilograms are the base SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif units for mass, not grams. gross error. Compare with systematic errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, random errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and mistakehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Gross errors are undetected mistakes that cause a measurement to be very much farther from the mean measurement than other measurements. hydrometer. An instrument for measuring the specific gravity of liquids. A hydrometer is a weight with a vertical scale attached. When placed into a liquid, the hydrometer bobs upright, and sinks to a certain level. The specific gravity or solution composition can be read from the liquid level on the vertical scale. Hydrometers are often calibrated in degrees Bauméhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. kelvin. (K) The SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif base unithttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of temperature, defined by assigning 273.16 K to the temperature at which steam, ice, and water are at equilibrium (called the triple point of water). The freezing point of water is 273.15 K. kilo-. (k) Prefix used in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system meaning "one thousand of". For example 1 km means "one thousand meters"; 2.8 kg could also be written "2.8 × 103 g" or "2800 g". limit of quantitation. (LOD) quantitative detection limit; limit of determination. The smallest detectable concentration an analytical instrument can determine at a given confidence level. IUPAChttp://antoine.frostburg.edu/chem/se...s/asterisk.gif defines the quantitative detection limit as Cld = ks/m, where k is 10, s is the standard deviation of instrument readings taken on a "blank" (a solution with zero concentration of analyte), and m is the slope of a plot of instrument response vs. concentration, as calculated by linear regression. mass. (m) Compare with weighthttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Mass is a measure of the tendency of an object to resist acceleration. It's harder to roll a tractor trailer than a roller skate; the tractor trailer has a far greater mass. measurement. Measurement is the collection of quantitative data. Measurement involves comparison of the quantity of interest with a standard called a unit. The comparison is never perfect. As a result, measurements always include error. You must consider the reliability of the measurement when using it to make decisions or estimate other quantities. mega-. (M) mega. SI prefix meaning "multiply by 106". For example, 3.2 MJ is 3200000 J. meter. (m) metre. The meter is the basic unit of length in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system of units, defined as the distance light travels through a vacuum in exactly 1/299792458 seconds. 1 m = 39.37 inches. Meters are abbreviated as "m" in measurements. micro-. (µ) micro. Prefix used in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system meaning "one millionth of". For example 1 µm means "one millionth of a meter"; 3.1 µL means "3.1 × 10-6 L". milli-. (m) Prefix used in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system meaning "one thousandth of". For example 1 mL means "one thousandth of a liter"; 1 mg means "one thousandth of a gram". mistake. blunder. Compare with systematic errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, random errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and gross errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A mistake is a measurement which is known to be incorrect due to carelessness, accidents, or the ineptitude of the experimenter. It's important to distinguish mistakes from errors: mistakes can be avoided. Errors can be minimized but not entirely avoided, because they are part of the process of measurement. Data that is mistaken should be discarded. Data that contains errors can be useful, if the sizes of the errors can be estimated. nano-. (n) Prefix used in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system meaning "multiply by 10-9". For example 1 nm means "0.000000001 m"; 2.8 ng could also be written "2.8 × 10-9 g". pico-. (p) Prefix used in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system meaning "multiply by 10-12". For example, 3 pm means 3× 10-12 meters. power. The rate at which energy is supplied. Power has define[SI] units of J/s, sometimes called "Watts" (W). precision. reproducibility. Compare with accuracyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Precision is reproducibility. Saying "These measurements are precise" is the same as saying, "The same measurement was repeated several times, and the measurements were all very close to one another". Don't confuse precision with accuracyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. random error. indeterminate error. Compare with systematic errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, gross errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and mistakehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Random errors are errors that affect the precision of a set of measurements. Random error scatters measurements above and below the mean, with small random errors being more likely than large ones. relative error. relative uncertainty. Compare with absolute errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The uncertainty in a measurement compared to the size of the measurement. For example, if three replicate weights for an object are 2.00 g, 2.05 g, and 1.95 g, the absolute error can be expressed as ± 0.05 g and the relative error is ± 0.05 g / 2.00 g = 0.025 = 2.5%. relative standard deviation. (RSD) Compare with standard deviationhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The relative standard deviation is a measure of precisionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, calculated by dividing the standard deviationhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif for a series of measurements by the average measurement. second. (s) The second (s) is the base unithttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of time in the SIhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif system of units, defined as the duration of 9,192,631,770 cycles of the radiation associated with a certain color of light emitted by the cesium atom. significant figure. significant digit; significant. A convention for recording measurements. Measurements are rounded so that they contain only the digits up to and including the first uncertain digit, when the number is written in scientific notation. SI. Systeme Internationale; International System. Le Systéme Internationale (SI) is a system of units introduced to remove barriers to international trade, based on the older metric system. It is now used in science and technical communications worldwide. specific gravity. specific gravities. Compare with densityhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The mass of a unit volume of a substance relative to the mass of a unit volume of water. Temperature must be specified when reporting specific gravities, since the density of the substance and of water change with temperature. Specific gravities are often reported relative to water at 4°C; at that temperature, water has a density of 1.00000 g/mL and the specific gravity of a substance is equal to its density in g/mL. specific volume. Compare with densityhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The volume of a unit mass of substance. For example, the specific volume of water at 4°C is 1.00000 mL/g. Specific volume is the reciprocal of density. standard deviation. (s,BESD,http://antoine.frostburg.edu/chem/se...ages/sigma.gif) The standard deviation is a statistical measure of precision. The best estimate of the standard deviation s for small data sets is calculated using http://antoine.frostburg.edu/chem/se...mages/sdev.jpg where xi is the measurement from the i-th run, x-bar is the mean of all the measurements, and N is the number of measurements. For very large data sets, the standard deviation is the root-mean-square deviation from the true mean, and is usually written as http://antoine.frostburg.edu/chem/se...ages/sigma.gif to distinguish it from the best estimate standard deviation s used for small data sets. systematic error. determinate error. Compare with random errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, gross errorhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and mistakehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Systematic errors have an identifiable cause and affect the accuracyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of results. trueness. Compare with accuracyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Trueness is the closeness of an average measurement to a "true" value, while accuracyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif is the the closeness of a single measurement to the true value. unit. A standard for comparison in measurements. For example, the meterhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif is a standard length which may be compared to any object to describe its length. weight. (W) Compare with masshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Weight is the force exerted by an object in a gravitational field. The weight of an object (W) arises from its masshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif (m): W = mg where g is the acceleration due to gravity (about 9.8 m/s2 on Earth). |
الدرس الثاني Matter
Matter absorption. http://antoine.frostburg.edu/chem/se...ages/sound.gifabsorb; absorbent. Compare with adsorptionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and sorptionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. 1. Penetration of molecules into the bulk of a solid or liquid, forming either a solution or compound. Absorption can be a chemical process (a strong solution of NaOH absorbs CO2 from the air) or a physical process (palladium absorbs hydrogen gas). 2. Capture and transformation of energy by a substance; for example, copper looks reddish because it absorbs blue light. An absorbent captures another material and distributes it throughout; an adsorbent captures another material and distributes it on its surface only. adsorbent. http://antoine.frostburg.edu/chem/se...ages/sound.gif Compare with absorbenthttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A substance that collects molecules of another substance on its surface. For example, gases that make water taste bad are strongly adsorbed on activated charcoalhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif granules in water filters. adsorption. http://antoine.frostburg.edu/chem/se...ages/sound.gifadsorb; adsorbed. Compare with absorptionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and sorptionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Adsorption is collection of a substance on the surface of a solid or a liquid. For example, gases that make water taste bad are strongly adsorbed on charcoal granules in water filters. aeration. http://antoine.frostburg.edu/chem/se...ages/sound.gifaerate. Preparation of a saturated solutionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of air gases by either spraying the solution in air or by bubbling air through it. aerosol. http://antoine.frostburg.edu/chem/se...ages/sound.gif Compare with colloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A colloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif in which solid particles or liquid droplets are suspended in a gas. Smoke is an example of a solid aerosol; fog is an example of a liquid aerosol. alkali metal. http://antoine.frostburg.edu/chem/se...ages/sound.gif (alkaline earth metal) alkali metal element. The Group 1 elements, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr) react with cold water for form strongly alkaline hydroxide solutions, and are referred to as "alkali metals". Hydrogen is not considered an alkali metal, despite its position on some periodic tables. alkaline earth. http://antoine.frostburg.edu/chem/se...ages/sound.gif An oxide of an alkaline earth metalhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, which produces an alkalinehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif solution in reaction with water. alkaline earth metal. http://antoine.frostburg.edu/chem/se...ages/sound.gif (alkali metal) The Group 2 elements, beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra) form alkaline oxides and hydroxides and are called "alkaline earth metals". allotrope. http://antoine.frostburg.edu/chem/se...ages/sound.gifallotropy; allotropic; allotropism. Compare with isotopehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and polymorphhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Some elements occur in several distinct forms called allotropes. Allotropes have different chemical and physical properties. For example, graphite and diamond are allotropes of carbon. alloy. http://antoine.frostburg.edu/chem/se...ages/sound.gifalloying; alloyed. Compare with amalgamhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A mixture containing mostly metals. For example, brass is an alloy of copper and zinc. Steel contains iron and other metals, but also carbon. amalgam. http://antoine.frostburg.edu/chem/se...ages/sound.gif Compare with alloyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. An alloyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif that contains mercury. analysis. http://antoine.frostburg.edu/chem/se...ages/sound.gifchemical analysis. Determination of the composition of a sample. atom. Compare with moleculehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and ionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. An atom is the smallest particle of an element that retains the chemical properties of the element. Atoms are electrically neutral, with a positively charged nucleus that binds one or more electrons in motion around it. boiling. Conversion of liquid into gas as bubbles of gas that form within the liquid. Boiling begins at the temperature where the vapor pressurehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of a liquid would be equal to the external pressure on the liquid. boiling point. http://antoine.frostburg.edu/chem/se...ages/sound.gif (bp) standard boiling point; normal boiling point. The temperature at which the vapor pressurehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of a liquid would be equal to the external pressure on the liquid. The standard boiling point is the temperature at which the vapor pressure of a liquid equals standard pressurehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. chemical change. reaction; chemical reaction. Compare with physical changehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A chemical change is a dissociation, recombination, or rearrangement of atoms. chemical property. http://antoine.frostburg.edu/chem/se...ages/sound.gifchemical properties. Compare with physical propertyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Measurement of a chemical property involves a chemical changehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. For example, determining the flammability of gasoline involves burning it, producing carbon dioxide and water. chromatography. http://antoine.frostburg.edu/chem/se...ages/sound.gif Chromatography is a method for separating mixtures based on differences in the speed at which they migrate over or through a stationary phasehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. colloid. http://antoine.frostburg.edu/chem/se...ages/sound.gif A colloid is a heterogeneous mixturehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif composed of tiny particles suspended in another material. The particles are larger than molecules but less than 1 µm in diameter. Particles this small do not settle out and pass right through filter paper. Milk is an example of a colloid. The particles can be solid, tiny droplets of liquid, or tiny bubbles of gas; the suspending medium can be a solid, liquid, or gas (although gas-gas colloids aren't possible). column chromatography. http://antoine.frostburg.edu/chem/se...ages/sound.gif Column chromatography is a method for separating mixtures. A solution containing the mixture is passed through a narrow tube packed with a stationary phasehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Different substances in the mixture have different affinities for the stationary phase, and so move through the tube at different rates. This allows the substances in the mixture to be detected or collected separately as they reach the end of the tube. compound http://antoine.frostburg.edu/chem/se...ages/sound.gif Compare with elementhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and mixturehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A compound is a material formed from elements chemically combined in definite proportions by mass. For example, water is formed from chemically bound hydrogen and oxygen. Any pure water sample contains 2 g of hydrogen for every 16 g of oxygen. concentration. Compare with dilutionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. 1. A measure of the amount of substance present in a unit amount of mixture. The amounts can be expressed as moleshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, masses, or volumes. 2. The process of increasing the amount of substance in a given amount of mixture. condensation. http://antoine.frostburg.edu/chem/se...ages/sound.gifcondensed. 1. The conversion of a gas into a liquid is called condensation. Condensation usually occurs when a gas is cooled below its boiling point. 2. A reaction that involves linking of two molecules with the elimination of water (or another small molecule). congener. 1. Elements belonging to the same grouphttp://antoine.frostburg.edu/chem/se...s/asterisk.gif on the periodic table. For example, sodium and potassium are congeners. 2. Compounds produced by identical synthesis reactions and procedures. crystallization. fractional crystallization; crystallisation. The process of forming pure crystalshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif by freezing a liquid, evaporating a solution, or precipitating a solid from solution. Impurities remain in the liquid, so crystallization is often to purify solid substances. density. http://antoine.frostburg.edu/chem/se...ages/sound.gif (http://antoine.frostburg.edu/chem/senese/images/rho.gif,d) Compare with specific gravityhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Mass of a substance per unit volume. Saying "the density of mercury is 13.55 g/cm3 " is the same as saying "the mass of exactly 1 cm3 of mercury is 13.55 g". dialysis. http://antoine.frostburg.edu/chem/se...ages/sound.gif Dialysis is the separation of components in a mixture by passing them across a semipermeable membranehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. diffusion. http://antoine.frostburg.edu/chem/se...ages/sound.gifdiffuse. Compare with effusionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The mixing of two substances caused by random molecular motions. Gases diffuse very quickly; liquids diffuse much more slowly, and solids diffuse at very slow (but often measurable) rates. Molecular collisions make diffusion slower in liquids and solids. dilution. http://antoine.frostburg.edu/chem/se...ages/sound.gif Adding solvent to a solution to lower its concentration. distillate. The vapor collected and condensed from a distillationhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. distillation. http://antoine.frostburg.edu/chem/se...ages/sound.gif Distillation is a technique for separating components of a mixture on the basis of differing boiling points. The mixture is heated, vaporizing some of the components. The vapor is collected and condensedhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif to isolate the components with the lowest boiling points. ductile. ductility. Compare with malleablehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Capable of being drawn into wire. Metals are typically ductile materials. electrolysis. http://antoine.frostburg.edu/chem/se...ages/sound.gif The process of driving a redox reactionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif in the reverse direction by passage of an electric current through the reaction mixture. electrorefining. Electrorefining is a method for purifying a metal using electrolysishttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. An electric current is passed between a sample of the impure metal and a cathodehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif when both are immersed in a solution that contains cationshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of the metal. Metal is stripped off the impure sample and deposited in pure form on the cathode. element Compare with compoundhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and mixturehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. An element is a substance composed of atoms with identical atomic numberhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The older definition of element (an element is a pure substance that can't be decomposed chemically) was made obsolete by the discovery of isotopeshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. element symbol. An international abbreviation for element names, usually consisting of the first one or two distinctive letters in element name. Some symbols are abbreviations for ancient names. emulsion. Compare with colloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A colloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif formed from tiny liquid droplets suspended in another, immisciblehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif liquid. Milk is an example of an emulsion. evaporation. vaporization. Conversion of a liquid into a gas. evaporate. To convert a liquid into a gas. extensive property. extensive; extensive properties. Compare with intensive propertyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A property that changes when the amount of matter in a sample changes. Examples are mass, volume, length, and charge. extraction. A technique for separating components in a mixture that have different solubilitieshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. For example, caffeine can be separated from coffee beans by washing the beans with supercritical fluid carbon dioxide; the caffeine dissolves in the carbon dioxide but flavor compounds do not. Vanillin can be extracted from vanilla beans by shaking the beans with an organic solvent, like ethanol. foam. Compare with colloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A colloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif in which bubbles of gas are suspended in a solid or liquid. Aerogel (solid smoke) and Styrafoam are examples of solid foams; whipped cream is an example of a liquid foam. fractional distillation. Compare with distillationhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A technique for separation of liquid mixtures by distillationhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif that uses a tower attached to a flask containing the mixture to perform multiple distillations. Vapor moving up the column condenses on packing material inside the column, trickles down the column, and again vaporises. The more volatilehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif component can then be drawn off at the top of the component, while the less volatile component remains at the bottom. gas. gases; vapor. Matter in a form that has low density, is easily compressible and expandable, and expands spontaneously when placed in a larger container. Molecules in a gas move freely and are relatively far apart. "Vapor" often refers to a gas made of a substance that is usually encountered as a liquid or solid; for example, gaseous H2O is called "water vapor". gel. Compare with colloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A gell is a solhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif in which the solid particles fuse or entangle to produce a rigid or semirigid mixture. For example, gelatin dissolved in water produces a sol of protein molecules. When the gelatin is cooked, the protein chains entangle and crosslink, forming a gel which is a mesh of solid protein with trapped pockets of liquid inside. Fruit jellies are also gels group. 1. A substructure that imparts characteristic chemical behaviors to a molecule, for example, a carboxylic acidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif group. (also: functional grouphttp://antoine.frostburg.edu/chem/se...s/asterisk.gif). 2. A vertical column on the periodic table, for example, the halogenshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Elements that belong to the same group usually show chemical similarities, although the element at the top of the group is usually atypical. heterogeneous mixture. heterogeneous. Compare with homogeneous mixturehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, solutionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, elementhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, and compoundhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A sample of matter consisting of more than one pure substancehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and more than one phasehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Blood, protoplasm, milk, chocolate, smoke, and chicken soup are examples of heterogeneous mixtures. high performance liquid chromatography. HPLC. An efficient form of column chromatographyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif that pumps a liquid solution of the sample at very high pressure through a column packed with a stationary phasehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif made of very tiny particles. The high pressure pumps required make HPLC an expensive technique. homogeneous mixture. solution. Compare with heterogeneous mixturehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, elementhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and compoundhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A sample of matter consisting of more than one pure substancehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif with properties that do not vary within the sample. intensive property. intensive; intensive properties. Compare with extensive propertyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A property that does not change when the amount of sample changes. Examples are density, pressure, temperature, color. ion exchange. ion exchange resin; ion exchanger. Ion exchange is a method of separating ions from a solution by reversibly binding them onto a resin that has charged sites on its surface. Ion exchangers are used to remove metal ions from drinking water. kinetic energy. Compare with potential energyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The energyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif an object possesses by virtue of its motion. An object of mass m moving at velocity v has a kinetic energy of ½mv2. lanthanide. Compare with actinidehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and inner transition metalshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Elements 57-70 are called lanthanides. Electrons added during the Aufbau constructionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of lanthanide atoms go into the 4f subshell. law of conservation of mass. There is no change in total mass during a chemical change. The demonstration of conservation of mass by Antoine Lavoisier in the late 18th century was a milestone in the development of modern chemistry. law of definite proportions. When two pure substances react to form a compound, they do so in a definite proportion by mass. For example, when water is formed from the reaction between hydrogen and oxygen, the 'definite proportion' is 1 g of H for every 8 g of O. law of multiple proportions. When one element can combine with another to form more than one compound, the mass ratios of the elements in the compounds are simple whole-number ratios of each other. For example, in CO and in CO2, the oxygen-to-carbon ratios are 16:12 and 32:12, respectively. Note that the second ratio is exactly twice the first, because there are exactly twice as many oxygens in CO2 per carbon as there are in CO. liquid. A state of matter that has a high density and is incompressible compared to a gas. Liquids take the shape of their container but do not expand to fill the container as gases do. Liquids diffusehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif much more slowly than gases. malleable. malleability. Compare with ductilehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Capable of being hammered into sheets. Metals are typically malleable materials. mass. (m) Compare with weighthttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Mass is a measure of the tendency of an object to resist acceleration. It's harder to roll a tractor trailer than a roller skate; the tractor trailer has a far greater mass. matter. Matter is anything that has mass. Air, water, coffee, fire, human beings, and stars are matter. Light, X-rays, photons, gravitons, information, and love aren't matter. metal. metallic. Compare with nonmetalhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and metalloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A metal is a substance that conducts heat and electricity, is shiny and reflects many colors of light, and can be hammered into sheets or drawn into wire. Metals lose electrons easily to form cationshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. About 80% of the known chemical elements are metals. molecule. Compare with atomhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and ionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The smallest particle of an element or compound that retains the chemical properties of the element or compound. A molecule is a collection of chemically bound atomshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif with characteristic composition and structure. Making or breaking bondshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif in a molecule changes it into a new molecule. Ionic compoundshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif are not composed of molecules, because there is no distinct collection of ionshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif that are chemically bound in the crystal. nonparticulate. Not composed of distinct particles. nonmetal. (metal,metalloid) non-metal. A nonmetal is a substance that conducts heat and electricity poorly, is brittle or waxy or gaseous, and cannot be hammered into sheets or drawn into wire. Nonmetals gain electrons easily to form anionshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. About 20% of the known chemical elements are nonmetals. nonpolar. Having a relatively even or symmetrical distribution of charge. nonpolar molecule. A molecule in which the center of positive charge and the center of negative charge coincide. Examples are CCl4 and CO2; counterexamples are CHCl3 and H2O. particulate. Composed of distinct particles. Smoke is particulate; pure gases are not. periodic table. An arrangement of the elementshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif according to increasing atomic numberhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif that shows relationships between element properties. period. Rows in the periodic tablehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif are called periods. For example, all of the elements in the second row are referred to as 'second period elements'. All elements currently known fall in the first seven periods. phase. in phase; out of phase; wave phase. 1.A phase is a part of a sample of matter that is in contact with other parts but is separate from them. Properties within a phase are homogeneous (uniform). For example, oil and vinegar salad dressing contains two phases: an oil-rich liquid, and a vinegar-rich liquid. Shaking the bottle breaks the phases up into tiny droplets, but there are still two distinct phases. 2. In wave motion, phase is the fraction of a complete cycle that has passed a fixed point since the current cycle began. The phase is often expressed as an angle, since a full cycle is 360^deg; (2 http://antoine.frostburg.edu/chem/senese/images/pi.gif). Two waves are "in phase" if the peaks of one wave align with the peaks of the other; they are "out of phase" if the peaks of one wave align with the troughs of the other. phase boundary. A phase boundary is a surface where two samples of matter with different properties are in contact. The surface of a gas bubble in water or the surface of a crystal are examples of phase boundaries. physical change. Compare with chemical changehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A change which does not transform one substance into another. For example, freezing water is a physical change because both water and ice are H2O. However, electrolysishttp://antoine.frostburg.edu/chem/se...s/asterisk.gif of water would not be a physical change because passing a strong electric current through water can decompose it into H2 and O2. physical property. physical properties. Compare with chemical propertyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Measurement of a physical property may change the arrangement but not the structure of the molecules of a material. Examples of physical properties are density, color, boiling point, volume, temperature, and mass. plasma. 1. In biology, the fluid in which blood cells or lymph cells are suspended. 2. A gaslike state of matter consisting of positively charged ions, free electrons, and neutral particles. Plasma is found in stars, the sun, the solar wind, lightning, and fire. polymorph. polymorphism; polymorphic. Compare with isotopehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and allotropehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Solid substances that occur in several distinct forms. Polymorphs have different chemical and physical properties. allotropeshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif are polymorphs of elements. potential energy. Compare with kinetic energyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. energyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif an object possesses by virtue of its position. For example, lifting a mass mby h meters increases its potential energy by mgh, where g is the acceleration due to gravity. precipitate. (http://antoine.frostburg.edu/chem/se.../downarrow.gif) ppt. An insolublehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif substance that has been formed from substances dissolved in a solution. For example, mixing silver nitrate and sodium chloride solutions produces a precipitate, insoluble silver chloride (along with soluble sodium nitrate. precipitation. Precipitation is the conversion of a dissolved substance into insoluble form by chemical or physical means. pure substance. substance. A sample of matter that cannot be separated into simpler components without chemical changehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Physical changes can alter the state of matterhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif but not the chemical identity of a pure substance. Pure substances have fixed, characteristic elemental compositions and properties. qualitative analysis. Compare with quantitative analysishttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A chemical analysis that detects the presence of a substance in a sample. quantitative analysis. Compare with qualitative analysishttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A chemical analysis that determines the concentration of a substance in a sample. sedimentation. Separation of a dense material (usually a solid) from a less dense material (usually a liquid) by allowing the denser material to settle out of the mixture. semipermeable membrane. A membrane that allows some but not all of the components in a mixture to pass through it. Semipermeable membranes are used in dialysishttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. sol. A colloidhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif with solid particles suspended in a liquid. Examples are protoplasm, starch in water, and gels. solid. A solid is a relatively dense, rigid state of matter, with a definite volume and shape. Molecules in solids are often packed close together in regularly repeating patterns, and vibrate around fixed positions. soluble. Compare with insolublehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Capable of being dissolved in a solventhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif (usually water). soluble salt. An ionic compoundhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif that dissolves in a solventhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif (usually water). solution. homogeneous mixture. Compare with heterogeneous mixturehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A sample of matter consisting of more than one pure substancehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif with properties that do not vary within the sample. Also called a homogeneous mixture. solvent. The most abundant component in a solutionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. solvent extraction. Solvent extraction is a method for separating mixtures by exploiting differences in the solubilities of the components. For example, a coffee machine extracts the soluble components of ground coffee with water, and leaves the insoluble components behind. The sample is shaken or mixed with solvent (or with two immiscible solvents) to effect the separation. The "like dissolves like" is a useful guide for selecting solvents to use in the extraction. Nonpolar substances are usually successfully extracted into nonpolar solvents like hexane or methylene chloride. Polar and ionic substances are often extracted with water. sorption. Compare with adsorptionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and absorptionhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. Assimilation of molecules of one substance by a material in a different phase. Adsorption (sorption on a surface) and absorption (sorption into bulk material) are two types of sorption phenomena. state of matter. There are three common states of matter: gaseshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, liquidshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif, and solidshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. States of matter differ in the way the molecules are arranged at the molecular level, but not in the structure of the molecules themselves. Other states (the plasma and Bose-Einstein condensate states) are uncommon on Earth. stationary phase. A stationary phase is a substance that shows different affinities for different components in a sample mixture in a separation of the mixture by chromatographyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. The mobile phase (a solution containing the sample) flows over or through the stationary phase to effect the separation. stoichiometry. 1. Ratios of atoms in a compound. 2. Ratios of moles of compounds in a reaction. 3. A branch of chemistry that quantitatively relates amounts of elements and compounds involved in chemical reactions, based on the law of conservation of masshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif and the law of definite proportionshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. stripping. Stripping is a technique for removing volatilehttp://antoine.frostburg.edu/chem/se...s/asterisk.gif components in a mixture by bubbling a stream of an chemically unreactive gas (like nitrogen) through the sample, and then 'scrubbing' the nitrogen through a solution or solid adsorbenthttp://antoine.frostburg.edu/chem/se...s/asterisk.gif that can recover the volatile materials. sublimation. sublimate; sublimating. Conversion of a solid directly into a gas, without first melting into a liquid. thin layer chromatography. (TLC) Compare with chromatographyhttp://antoine.frostburg.edu/chem/se...s/asterisk.gif. A technique for separating components in a mixture on the basis of their differing polarities. A spot of sample is placed on a flat sheet coated with silica and then carried along by a solvent that soaks the sheet. Different components will move different distances over the surface. TLC is a useful screening technique in clinical chemistry; for example, it can be used to detect the presence of drugs in urine. transition metal. transition element; outer transition element. An element with an incomplete d subshell. Elements which have common cationshttp://antoine.frostburg.edu/chem/se...s/asterisk.gif with incomplete d subshells are also considered transition metals. Elements with incomplete f subshells are sometimes called "inner transition elements". zone refining. A method for purifying solids based on the fact that solutes tend to concentrate in the liquid when a solution is frozen. A solid bar is drawn slowly over a heat source and melted in a narrow band; impurities are carried along in the melted band until the end of the bar is reached. |
كتاب كيمياء عامه رائع
1 مرفق
السلام عليكم
كتاب كيمياء عامه رائع كله يشوف |
انا متشكره جدا لمجهود حضرتك استاذ عاطف والعضو ستار
فى رعايه الله |
شكرااااااااااااااااااااااااااااا دكتور عاطف ولكني انتظر منك الكثير انا لسه طالب في اولي علوم جيلوجيا ممكن توجهني لكي استفيد بعطائك وكتبك لأني مش عارف اتعامل معها او استفيد منها كما اتمني وببساطه الأنجليزي عاملي مشكله كبيره فلو سمحت ممكن توجهني وشكراااااااااااااااااااااااااااااااااااا وتحاول تشرح كتبك شكرااااااااااااااااااااااااااااااااااااااااااااااا اااااااااا وكيفية استخدمها شكرااااااااااااااااااااااااااااااااااااااااااااااا اااااااااا وتكتب كل تخصص مفيد ليها هذه الكتب والدروس والمحاضرات اللي حضرتك تكتبها وربنا يكرمك يااااااااااااااا رب
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بجد جزاك الله كل خير مستر عاطف مجهوود جاامد:) انا فهمت الحمد لله جزء من اللى حضرتك شارحه (ده انجاز لانه متشرحش هندنا لسه فى الكلية):bosyht9: بس بجد اكتر استفادة كتاب الكيميا العام:mellow: بجد مفيد جدااا جزاك الله خير مستر عاطف:) |
شكرااااااااااااااااااااااااااااا دكتور عاطف ولكني انتظر منك الكثير انا لسه طالب في اولي علوم جيلوجيا ممكن توجهني لكي استفيد بعطائك وكتبك لأني مش عارف اتعامل معها او استفيد منها كما اتمني وببساطه الأنجليزي عاملي مشكله كبيره فلو سمحت ممكن توجهني وشكراااااااااااااااااااااااااااااااااااا وتحاول تشرح كتبك شكرااااااااااااااااااااااااااااااااااااااااااااااا اااااااااا وكيفية استخدمها شكرااااااااااااااااااااااااااااااااااااااااااااااا اااااااااا وتكتب كل تخصص مفيد ليها هذه الكتب والدروس والمحاضرات اللي حضرتك تكتبها وربنا يكرمك يااااااااااااااا رب انتظر منك رد
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ميرسى اوى لحضرتك على مجهودك معانا
وربنا يجعله فى ميزان حسناتك |
شكرااااااااااااااااااااااااااااا دكتور عاطف ولكني انتظر منك الكثير انا لسه طالب في اولي علوم جيلوجيا ممكن توجهني لكي استفيد بعطائك وكتبك لأني مش عارف اتعامل معها او استفيد منها كما اتمني وببساطه الأنجليزي عاملي مشكله كبيره فلو سمحت ممكن توجهني وشكراااااااااااااااااااااااااااااااااااا وتحاول تشرح كتبك شكرااااااااااااااااااااااااااااااااااااااااااااااا اااااااااا وكيفية استخدمها شكرااااااااااااااااااااااااااااااااااااااااااااااا اااااااااا وتكتب كل تخصص مفيد ليها هذه الكتب والدروس والمحاضرات اللي حضرتك تكتبها وربنا يكرمك يااااااااااااااا رب انتظر منك رد
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Emily Watson
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Kimberly Walsh
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يا جماعه انا لسا داخل اولى ومش فاهم اى حاجه بجد يا ريت حد يفهمنى ايه الشرح ده كله وهل الدراسه هتبقا كلها كدا ولا ايه ربنا يستر بجد
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مشكووووووووووور
و في انتظار المزيييييييييييييد |
شكرااااااااااااا كتير
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شكرا جزيلا
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اولا شكرا دكتور عاطف
تانيا هو ده يعتبر كل المنهج لاولى |
1st time posting here
Just wanted to say hello all. This is my first post.I would like to learn a lot here.______________________Hydrolyze
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طالب زهقان
هل كليه العلوم كلها انجلش ولا في مواد عربي
والمواد الانجليزي في المحاضره الدكتور بيشرحها عربي ولا انجليزي وهل الملخصات الي بتعملها الدكتره بتكون مترجمه ولا ايه علشان في ناس كتير ضعيفه في الانجليزي ياريت حد يرد عليا بسرعه ويرد علي كل سؤال لوحده علشان المعلومات متخشش علي بعض اسف علي التطويل في الكلام ............................................... طالبك العزيز والجديد sary elmasry |
بجد مرسى كنت محاجة الحاجات دى اوى عندى بحث
لو سمحت عايزة اسم كتاب اساسيات كيميا بس يكون انجليزى يدينى فكرة عامة عن الكيميا عامة |
اقتباس:
والدكتور لما بيشرح بيشرح من دة ع دة بحيث يوصل المعلومه اول شهريين تلاته بس ع ماتتاقلم وبعدها مش هتعرف تذاكر الا بالانجلش الملخصات او مذكرات هتبيقي طبعا الانجلش وزى ماقلتك شويه وهتتاقلم |
ممكن شرح للتكامل لاولى علوم للضرورة
وجزاكم الله كل خير |
هل منهج الكيمياء موحد على مستوى كليات العلوم فى الجامعات؟
عشان احنا معندناش الحاجات دى والشرح بالعربى واحنا عندنا كتابين للكيمياء واسمها كيمياء فيزيائية |
اقتباس:
بس في الاربع سنين بتلاقي كل المواد للي هنا هى هنا ولو اختلفوا هيختلفوا في مادتين تلاته بالكتير وبالنسبه للشرح فدة بيتوقف ع الدكتور نفسه بيشرح ازاى لكن اغلب الدكاترة بتشرح انجليزى ع عربي بحيث يوصلك المعلومه |
ربنا يبارك فيك وفى امثالك
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الكبير 00كبير 00خالص تحياتي لأخي الفاضل د/ عاطف خليفة 00مع دعواتي بأن ينعم عليه الله بالصحة والعافية 0
أخوك / محمد عوض النشار |
الكبير 00كبير 00خالص تحياتي لأخي الفاضل د/ عاطف خليفة 00مع دعواتي بأن ينعم عليه الله بالصحة والعافية 0
أخوك / محمد عوض النشار |
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يا جدعااااااان الكيميا سهله جدا يعنى وانا ف المحاضرة مع الدكتورة تماما وفاهم وكلوا زى الفل ...اجى بقى اذاكر الاقى كلمات انجليزى مكلكعه وحاجات بايخه ازهق واقفل الكتاب علللللللى طول ...يعنى المواد سهله بس التأقلم مع الانجليزى العلمى بايخ شويه بس هيجى لاااااازم يجى
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مشكوووووووووووووووووووووووووووووووووووووووووووووور
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وجزاك الله خيرا
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