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Phase Diagrams A phase diagram allows for the prediction of the state of matter at any given temperature & pressure. Key aspects: -critical point -normal boiling point -triple point. SPECIFIC HEAT re-visited. The quantity of heat required to raise the temperature of one
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Phase Diagrams A stage graph takes into account the expectation of the condition of matter at any given temperature & weight. Key perspectives: - basic point - typical breaking point - triple point

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SPECIFIC HEAT returned to The amount of warmth required to raise the temperature of one gram of a substance by one degree Celsius (or one Kelvin) q = s x m x T ENTHALPY OF A PHASE CHANGE The warmth vitality required to experience an adjustment in stage happens at consistent temperature and is connected with the normal change in separation between atoms. For water: Hº fus = 335 J/g or 6.02 kJ/mol Hº vap = 2260 J/g or 40.7 kJ/mol

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HEATING - COOLING CURVE Calculate the measure of vitality required to change over 50.0 g of ice at 0.0 ºC to steam at 100.0ºC H vap g 100 - T ( o C) 0 - l H fus s Energy (J) q add up to = q (s) + D H fus + q (l) + D H vap + q (g)

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Water and the Changes of State Q. What number of kilojoules of vitality are expected to change 15.0 g of ice at - 5.00 o C to steam at 125.0 o C? The initial step is to plan a pathway: q 1 = ms D T for ice from - 5.0 to 0.0 o C, the particular warmth of ice is 4.213 J/g o C q 2 = D H fus for ice to fluid at 0.0 o C q 3 = ms D T for fluid 0.0 o C to 100.0 o C q 4 = D H vap for fluid to steam at 100.0 o C q 5 = ms D T for steam 100.0 to 125.0 o C; the particular warmth of steam is 1.900 J/g o C so q T = q 1 + q 2 + q 3 + q 4 + q 5 The following stride is to ascertain every q: q 1 = (15.0 g) (4.213 J/g o C) (0.0 - (- 5.0) o C) = 316 J q 2 = (335 J/g) (15.0 g) = 5025 J q 3 = (15.0 g) (4.184 J/g o C) (100.0 - (0.0) o C) = 6276 J q 4 = (2260 J/g) (15.0 g) = 33900 J q 5 = (15.0 g) (1.900 J/g o C) (110 - 100 o C) = 285 J q T = 316 J + 5025 J + 6276 J + 33900 J + 285 J = 45.8 kJ

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INTERMOLECULAR FORCES INTRAMOLECULAR > INTERMOLECULAR (covalent, ionic) (van der Waals, and so on) " between particles" " between atoms" TYPES Neutral Molecules: 1. Dipole-dipole strengths 2. London Dispersion 3. Hydrogen holding Ions: 1. Particle dipole constrain

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INTERMOLECULAR FORCES STRENGTH: BOILING POINTS AND MELTING POINTS ARE DEPENDENT ON STRENGTH OF INTERMOLECULAR FORCES . Solid FORCE  HIGH BOILING POINT Type of interaction Approximate Energy (kJ/mol) Intermolecular van der Waals 0.1 to 10 (London, dipole-dipole) Hydrogen bonding 10 to 40 Chemical holding Ionic 100 to 1000 Covalent 100 to 1000

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ION-DIPLE FORCES -amongst particles and polar atoms -quality is reliant on charge of the particles or extremity of the bonds -generally included with salts & H 2 0 DIPOLE-DIPOLE FORCES -between nonpartisan polar atoms -weaker drive than particle dipole -positive dipole pulled in to negative dipole -atoms ought to be moderately near one another -quality is subject to extremity of securities. LONDON DISPERSION FORCES -all particles and mixes -includes momentary dipoles -quality is subject to Molar Mass (size) -contributes more than dipole-dipole -shape adds to quality

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HYDROGEN BONDING AN INTERMOLECULAR ATTRACTION THAT EXISTS BETWEEN A HYDROGEN ATOM IN A POLAR BOND AND An UNSHARED ELECTRON PAIR ON A NEARBY ELECTRONEGATIVE SPECIES, USUALLY O , F , and N NOTE: (An exceptional sort of dipole-dipole collaboration) - more grounded than dipole-dipole and London scattering strengths - Accounts for water\'s surprising properties -high breaking point -strong Less thick than fluid -widespread dissolvable -high warmth limit

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FLOWCHART OF INTERMOLECULAR FORCES Interacting atoms or particles Are polar Are particles Are polar particles included? particles included? what\'s more, particles both exhibit ? Are hydrogen molecules clung to N, O, or F iotas? London strengths Dipole-dipole hydrogen holding Ion-dipole Ionic just (prompted powers Bonding dipoles) Examples: Examples Example: Examples: Ar(l), I 2 (s) H 2 S, CH 3 Cl fluid and strong KBr in NaCl, H 2 O, NH 3 , HF H 2 O NH 4 NO 3 NO YES NO YES NO Van der Waals powers

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PROPERTIES OF LIQUIDS VISCOSITY -The resistance of a fluid to stream -Depends on appealing powers between atoms and basic elements which cause more noteworthy communication (trap). SURFACE TENSION -The vitality required to expand the surface region of a fluid by a unit sum (E/A) -Due to cooperations amongst particles and the absence of association if there are no atoms to communicate with.

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VAPOR PRESSURE The weight applied by a vapor in harmony with its fluid or strong state. 1. Vapor weight changes with intermolecular powers and temperature 2 . Vapor weight includes a dynamic harmony fluid gas 3. Unpredictable versus nonvolatile 4. Clausius - Clapeyron condition - relates vapor weight and fluid temperature

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CLAUSIUS - CLAPEYRON EQUATION all in all, the higher the temperature, the weaker the intermolecular powers, and hence the higher the vapor weight. The non-straight relationship between vapor weight and temperature is given by the Clausius - Clapeyron condition. In P = (- H vap/RT) + C : a straight line if lnP versus 1/T It depicts the measure of vitality required to vaporize 1 mole of particles in the fluid state R = 8.31 J/mol K T = Kelvin P = vapor weight In P 2 = - H vap 1 - 1 P 1 R T 2 T 1 Q. The vapor weight of ethanol at 34.9ºC is 100.0 mmHg and at 78.5ºC it\'s 760.0 mmHg. What is the warmth of vaporization of ethanol?

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CYRSTALLINE SOLIDS Type of solid grid site Type of force properties of illustrations molecule sort between particles solids IONIC positive & electrostatic high M.P. NaCl negative particles fascination nonvolatile Ca(NO 3 ) 2 hard & weak poor conductor POLAR polar dipole-dipole & direct M.P. Sucrose, MOLECULAR atoms London Dispersion moderate C 12 H 22 O 11 powers instability Ice, H 2 O NONPOLAR Nonpolar London Dispersion low M.P., Argon, Ar, MOLECULAR molecules & strengths volatile Dry Ice, CO 2 iotas MACRO- atoms covalent bonds extremely high Diamond, C MOLECULAR between atoms M.P. nonvolatile Quartz, SiO 2 Covalent- Arranged in Very Hard Network Network Poor transmitter METALLIC metal particles fascination between variable M.P. Cu, Fe external electrons low volatility Al, W and positive great conduit nuclear focuses

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TYPE OF MELTING POINT HARDNESS ELECTRICAL SOLID OF SOLID & BRITTLENESS CONDUCTIVITY Molecular Low soft & brittle Nonconducting Metallic Variable Variable hardness, leading pliant Ionic High to extremely hard & brittle Nonconducting high strong (directing fluid) Covalent Very high Very hard Usually Network nonconducting

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CRYSTALLINE SOLIDS - Composed of gem cross sections - the geometric course of action of grid purposes of a gem comprises of unit cells - littlest unit from which iotas can be stacked in 3-D - unit cells (there are distinctive sorts; see transparencies) - edge lengths and edges are utilized to portray the unit cell 3 sorts of unit cells -primitive (straightforward) -body focus cubic -confront focused cubic - metals and salts are generally cubic Ni = FCC Na=BCC NaCl=FCC In FCC corners and face are imparted to different units Question: Determine the net number of particles in LiF (FCC) Li + = 1/4 (Li per edge) (12 edges) = 3 1 (focus) (1 focus) = 1 F - = 1/8 (per corner) (8 corners) = 1 1/2 (confront) (6 faces) = 2

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MOLECULAR SOLIDS - solidified respectable gasses, Ne - needs substantial number of particles encompassing community for most extreme fascination (see straightforwardness) - close pressing game plan varieties: - hexagonal close-pressing structure (ABABABA… ); 6-unit cell (hcp) - cubic close-stuffed structure (ccp); ABC ... Like FCC Coordination number = the quantity of closest neighbors; 12 for close-pack structures METALLIC SOLIDS - ocean of electrons; delocalized (holding is non-directional) - many metals are cubic or hexagonal close-pressed gems COVALENT NETWORK - directional covalent bonds - precious stone, Si, Ge, dark Sn are tetrahedral, sp3 hybridized, FCC -graphite is hexagonal level sheets; sp2 hybridized; electrical properties are expected to the expanded delocalization of the electrons.

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X-RAY DIFFRACTION - Determining gem structure x-beam diffraction used to acquire structure of proteins (1962 Nobel Prize myoglobin) & hemoglobin - Due to request structure - gems comprises of rehashing planes - Planes go about as reflecting surfaces - X-beam reflecting off surface makes diffr

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