State of matter characteristics solid Retains shape and volume

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1 **See attachment fr graphs States f matter The fundamental difference between states f matter is the distance between particles Gas Ttal disrder Much empty space Particles have cmpletely freedm f mtin Particles far apart Liquid Disrder Particles r clusters f particles are free t mve relative t each ther Particles clse tgether Slid Ordered arrangement Particles are essentially in fixed psitins Particles clse tgether Because in the slid and liquid states particles are clse tgether we refer t them as cndensing phases The state a substance is in at a particular temperature and pressure depends n tw adversarial entities Kinetic energy (energy f mvement) Strength f attractin between particles Characteristics State f matter characteristics slid Retains shape and vlume Virtually incmpressible Desn t flw Diffusing within a slid ccurs extremely slwly liquid Assumes the shape f the prtin f the cntainer it ccupies Desn t expand t fill cntainer Virtually incmpressible Flws readily Diffusin ccurs slwly gas Assumes bth the vlume and shape f its cntainer Is cmpressible Flws readily Diffusin within a gas ccurs rapidly Heating curves At a phase change there is n change in temperature Why? Energy is ging int the phase change The heat added t the melting and biling pints ges int pulling the mlecules further apart frm each ther 1

2 **See attachment fr graphs Frces Phase diagrams Displays the state f a substance at varius pressures and temperatures and places where equilibria exist between phases Triple pint: exists in all three states f matter at the same time Critical pint: abve it liquids and vaprs are indistinguishable Belw triple pint: cannt be a liquid Phase diagram f water The slpe f the slid-liquid line is negative Intermlecular: frces between particles Intramlecular: frces within a particle, bnds Ranking f MP/BP f a substance Highest Netwrk Cvalent High Inic Metallic Mid Hydrgen Bnding Lw Diple-diple Lwest Lndn Dispersin Frces Vapr pressure: the pressure exerted by a vapr at equilibrium with its slid r liquid at a given temperature Vapr pressure increases as temperature increases As temperature increases, mre particles will have enugh kinetic energy t becme a vapr, the mre vapr the mre cllisins that will ccur s the vapr pressure will rise Vlatile vs. Nn vlatile Vlatile Easily evaprates Lw biling pint Weak intermlecular frces Ex) methane, rubbing alchl Nn vlatile Desn t easily evaprate High biling pint Strng intermlecular frces Ex) water Biling/Vaprizatin vs. Evapratin Biling: ccurs when vapr pressure f the liquid is equal t the vapr pressure f the atmsphere Evapratin Liquid t gas belw the biling pint Takes place at the surface Highest valence electrns escape: cling prcess Kinetic Mlecular Thery f Gases The 5 Pstulates 2

3 **See attachment fr graphs Gas particles are much smaller than the distance between them Althugh small, they still have mass Gas particles are in cnstant, rapid, randm mtin Mve in a straight line until they cllide with each ther r with the walls f the cntainer Fills the cntainer and quickly diffuse frm ne area t anther Cllisin f gas particles with each ther r with the walls f the cntainer are perfectly elastic (n lss f energy) N kinetic energy is lst when gas particles cllide N energy f mtin is lst Gas particles d NOT attract r repel each ther Because they are mving quickly and are far apart The average kinetic energy f the gas particles depends nly n the temperature f the gas The kinetic energy f a gas is prprtinal t their temperature in kelvin If the temperature ges up kinetic energy ges up If the temperature ges dwn the kinetic energy ges dwn IMPORTANT NOTE: any tw gases at the same temperature will have the same kinetic energy! (i.e. they are mving at the same speed) Standard pressure Pressure is measured by the number f cllisins f gas particles Mre cllisins mre pressure Less cllisins less pressure Units 1 atm = kilpascals (kpa) = 760 millimeters f mercury (mmhg) = 760 Trr Daltn s law f partial pressures The pressure f each gas in a mixture is called the partial pressure f that gas Law: the ttal pressure f a mixture f each f the cmpnent gases P ttal = P 1 + P 2 + P Cllecting a gas ver water In rder t cllect the gas prduced in a chemical reactin, that gas is bubbled thrugh water and cllected in a separate cntainer The ttal pressure inside the cntainer isn t just the gas because sme water has evaprated and is adding pressure t the gas The ttal pressure inside the cntainer, then, is the pressure f the gas and the pressure f the water vapr Effusin and Diffusin ALWAYS HIGH TO LOW Effusin: the mvement f gas thrugh a very small hle int a vaccum Rates f effusin 3

4 **See attachment fr graphs Gas partivles that mve faster will effuse at a faster rate Gas particles with smaller mlar masses have higher average velcities than d gases with larger mlar masses, when at the same temperature Frmula: rate 1 = rate 2 MM 2 MM 1 Rate 1: effusin rate f gas 1 Rate 2: effusin rate f gas 2 MM 2: mlar mass f gas 2 MM 1: mlar mass f gas 1 LIGHTER GAS ON TOP!!! (fr rate) Diffusin: the mvement f ne type f gas int anther type f gas Lighter mlecules will escape faster than heavier mlecules Mle fractin: a dimentinless quantity that expresses the rati f the number f mles f ne cmpund t the number f mles f all cmpunds present Symbl: X ALWAYS less than 1 The partial pressure f Gas A = (mle fractin f Gas A) * (ttal pressure) Avgadr s law Equal vlumes f gases at the same temperature and pressure cntain equal numbers f particles V 1 = V 2 n 1 n 2 Gas Laws Byle: P 1 V 1 = P 2 V 2 Charles: V 1 = V 2 T 1 T 2 Gay Lussac: P 1 = P 2 T 1 T 2 Cmbined Gas Law: P 1V 1 = P 2V 2 n 1 T 1 n 2 T 2 Ideal Gas Law: PV=nRT Variatins PM = DRT PV = (m/m)rt Ideal cnditins 1 atm, 22.4 L, 273 K, 1 ml Particles take up n space and n vlume N IMFs between particles Wn t liquefy (n vlume) Gas cnstant (R): L*atm / k*ml Real gases All gas particles have vlume All gases have IMFs Turns int a liquid when cndensed 4

5 **See attachment fr graphs Behaves like an ideal gas when... high temperature (rapid randm mvement) lw pressure (particles further apart) Gas Stichimetry At STP One mle f a gas has a vlume f 22.4 Liters Vlume t vlume under any cnditins Use Avgadr s law All ther Stichimetry Use ideal gas law (PV=nRT) Type f Substance IMF r IPF Descriptin Examples Prperties Inic (metal and nnmetal) Plar Cvalent (nnmetals) Electrstatic Attractin (inic bnding) IMP: diple-diple Strng bnd Slid Very rigid Crystalline lattice When brken up: anins and catins Plar (asymmetrical r uneven terminal atms) Attractin btwn ppsitely charged regins Weak bnd NaCl KCl CaO HCl HBr CH2O 1. sluble in water 2. electrlyte 3. hard & brittle 4. Slid at rm temp 5. high MP and BP 1. sluble in water 2. melt/disslves 3. liquid at rm temp 4. lw MP and BP 5. nn-electrlyte Nn-Plar Cvalent (nnmetals) IMF: Lndn dispersin frces Weak attractin (due t temprary shift in electrn clud) (induces nn-plar mlecule) Diatmics Nn-plar gases 1. insluble in water 2. lwest MP and BP 3. Gas at rm temp 4. nn-electrlyte 5. disslves in NP slvent Metallic (metal) Metallic bnd Electrns are free t mve thrughut the catin Sea f Electrns Strng charge f attractin Cu Ag Au Zn 1. insluble in water 2. cnducts electricity 3. shiny & malleable 4. ductile 5. slid at rm temp 6. high MP and BP Netwrk Cvalent (very strng bnds) Cvalent btwn particles Repeating pattern in all directins Carbn and Sulfur Diamnd Quartz Sand Graphite 1. desn t disslve ever 2. hard & brittle 3. Highest MP and BP Plar Cvalent (nnmetals) IMF: Hydrgen Bnds (type f diple-diple) Strngest f d-d Must inclued N, F, r O and H HF NH3 H2O 1. sluble in water 2. nn-electrlyte 3. lw/mid MP and BP 5