Bell Ringer What is the difference between the different states of matter? [in terms of energy or...

Bell Ringer What is the difference between the different states of matter? [in terms of energy or particles]

based on the idea that particles are constantly moving can be applied to solid, liquid, or gas provides a model of ideal gas behavior so it is only an approximation Real student Ideal student

1. Gases consist of tiny particles that are very far apart most volume is empty space low density allows gases to be easily compressed 2. All collisions between particles and container walls are elastic there is no net loss of energy when particles collide total kinetic energy stays constant even though it can be transferred between particles

3. Particles are in continuous, rapid, random motion since they are moving, they have KE KE overcomes their attractive forces 4. No forces of attraction or repulsion YOU ARE ATTRACTED TO EVERYTHING!

Average kinetic energy depends on temperature KE increases as temperature increases At the same T, lighter particles have higher speeds than heavier ones velocity and temperature are directly proportional

ideal gas is defined by the KMT most gases behave close to the ideal when there is: HIGH temperature so they have enough KE to overcome attractive forces HIGH temperature so they have enough KE to overcome attractive forces Low pressure so they are very spread out Low pressure so they are very spread out Gases with little attraction, low mass, are more ideal (monatomic gases)

Create a cartoon that helps to explain the KMT to other students! Grade will be based upon: CreativityEffort Use of color

Bell Ringer List the 4 parts of the KMT.

P : amount of force in an area Why would shoes with smaller diameter heel not be allowed on gym floor? As surface area decreases, pressure increases Pressure exerted by a gas depends on volume volume temperature temperature number of molecules number of molecules

STANDARD TEMPERATURE & PRESSURE STP Standard Temperature = 0C Standard Pressure = 1 atm

Pressure and Temperature STP (Standard Temperature and Pressure) standard temperaturestandard pressure 1 atm 101.3 kPa 760 mm Hg 273 K 0oC0oC Equations / Conversion Factors: K = o C + 273 o C = K 273 1 atm = 101.3 kPa = 760 mm Hg = 760 torr

Conversions Convert 25 o C to Kelvin. K = o C + 273 How many mm Hg is 231.5 kPa? How many kPa is 1.37 atm? 25 o C + 273 298 K = X kPa = 1.37 atm 101.3 kPa 1 atm = 138.8 kPa X mm Hg = 231.5 kPa 760 mm Hg 101.3 kPa = 1737 mm Hg

Practice Conversions

Is the pressure of the vapor over a liquid (and some solids) at equilibrium Must be in contact with a liquid otherwise you just have a gas! Must be in contact with a liquid otherwise you just have a gas! Depends on temperature only Depends on temperature only

Vapor Pressure more sticky less likely to vaporize In general: LOW v.p. not very sticky more likely to vaporize In general: HIGH v.p. measure of the tendency for liquid particles to enter gas phase at a given temp. a measure of stickiness of liquid particles to each other NOT all liquids have same vapor pressure at same temp.

Bell Ringer If the pressure inside a tire is 248 kPa, how many millilmeters of mercury is that? 1860

DEMOS Vapor Pressure manometer

Behavior of a liquid in a closed container

Boiling Point Explained 020406080 100 0 20 40 60 80 100 TEMPERATURE ( o C) PRESSURE (kPa) CHLOROFORM ETHANOL WATER Volatile substances evaporate easily (have high v.p.s). BOILING when vapor pressure = confining pressure (usually from atmosphere) b.p. = 78 o C b.p. = 100 o C atmospheric pressure is 101.3 kPa

Formation of a bubble is opposed by the pressure of the atmosphere

Boiling vs. Evaporation Boiling point: atmospheric pressure = vapor pressure Evaporation: molecules go from liquid to gas phase Evolutionary process - slow Revolutionary process - fast Lyophilization freeze drying AIR PRESSURE 15psi VAPOR PRESSURE 15 psi liquid gas

Barometer Empty space (a vacuum) Hg Weight of the mercury in the column Weight of the atmosphere (atmospheric pressure) measures atmospheric pressure

Barometers Mount Everest Sea level On top of Mount Everest Sea level fraction of 1 atm average altitude (m)(ft) 100 1/25,48618,000 1/38,37627,480 1/1016,13252,926 1/10030,901101,381 1/100048,467159,013 1/1000069,464227,899 1/10000096,282283,076

Practice Vapor Pressure of 4 liquids wkst

1.What is one way you can make a real gas act more ideal? 2. 92.1 kPa = _______ mmHg 3. If ethanol boils at 82C, what is the atmospheric pressure? 4. In terms of pressure(s), when does a liquid boil? 5. Name of the two MOST ideal REAL gases?

1. Spread out, high temp or low press 2. 691mmHg 3. 110 kPa 4. When vp = atm pressure 5. H or He

Bell Ringer According to Reference Table H, at what temperature will propanone boil if the atmospheric pressure is 70kPa?

Evaporation H 2 O(g) molecules (water vapor) H 2 O(l) molecules

DEMOS Boiling Water Boiling with dec. VP Boiling Water With Ice

Show how pressure, volume, and temperature, are related to gases. REMEMBER

Hold whichever variable constant to adjust the other variable to see what would happen as a result of the desired change If the temperature remains constant and we lower the pressure, what must happen to the volume? The volume must increase!

If the temperature remains constant and we lower the volume, what must happen to the pressure? The pressure must increase!

Relationships between volume and pressure.

DEMOS Vacuum Pump

Boyles Law: P and V as one increases, the other decreases inversely proportional pressure is caused by moving molecules hitting container walls If V is decreased and the # of molecules stays constant, there will be more molecules hitting the walls per unit of time

Boyles Law

Pressure vs. Volume for a Fixed Amount of Gas (Constant Temperature) 0 100 200 300 400 500 Pressure Volume PV (Kpa) (mL) 100 500 50,000 150 333 49,950 200 250 50,000 250 200 50,000 300 166 49,800 350 143 50,500 400 125 50,000 450 110 49,500 Volume (mL) 100 200 300 400 500 600 Pressure (KPa)

Chuckys Law (aka Charles Law) Relationship between volume and temperature

Charles Law: V and T if P is constant, gases expand when heated when T increases, gas molecules move faster and collide with the walls more often and with greater force to keep the P constant, the V must increase

Example: Boyles Law Consider a 1.53L sample of gaseous SO 2 at a pressure of 5.6 x 10 3 Pa. If the pressure is changed to 1.5 x 10 4 Pa at constant temperature, what will be the new volume of the gas?

Practice 1. If the volume of a gas at 10.0 o C is 100.0 ml, then what is the volume at -2.0 o C? V 1 = V 2 T 1 T 2 100.0 ml 10.0 o C = V2V2 -2.0 o C 10.0 x V 2 -200 V 2 = -20. ml We cant have negative volumes, so we cant use a temperature scale with negatives = ALWAYS USE KELVIN With gas laws, ALWAYS USE KELVIN V 1 = V 2 T 1 T 2 100.0 ml 283 K = V2V2 271 K 283 x V 2 27100 V 2 = 95.7597 mL = T 1 = 10 o C V 1 = 100.0 mL V 2 = ? T 2 = -2.0 o C T 1 = 10 o C V 1 = 100.0 mL V 2 = ? T 2 = -2.0 o C 283 K 271 K 96 mL

Gas Laws pkt Vapor Pressure wkst

Charles Law: V and T Charles Law: the V of fixed mass of gas at constant P varies directly with temperature. What kind of graph is V vs. T?

Boyle's Law If n and T are constant, then PV = (nRT) = k This means, for example, that Pressure goes up as Volume goes down. Robert Boyle (1627 - 1691) Son of Early of Cork, Ireland. A bicycle pump is a good example of Boyle's law. As the volume of the air trapped in the pump is reduced, its pressure goes up, and air is forced into the tire.

Boyles Law 1 atm 4 Liters As the pressure on a gas increases 2 atm 2 Liters As the pressure on a gas increases - the volume decreases Pressure and volume are inversely related

Pressure-Volume Relationship 2.5 250 200 150 100 50 0 0.5 1.0 1.5 2.0 Volume (L) Pressure (kPa) (P 1,V 1 ) (P 2,V 2 ) (P 3,V 3 ) P 1 x V 1 = P 2 x V 2 = P 3 x V 3 = 100 L x kPa P 1 = 100 kPa V 1 = 1.0 L P 2 = 50 kPa V 2 = 2.0 L P 3 = 200 kPa V 3 = 0.5 L

P vs. V (Boyles Data)

Charles Law discovered by French physicist, Jacques Charles in 1787 first person to fill balloon with hydrogen gas and make solo balloon flight

Example: Charles Law & Temp. A sample of gas at 15.0C and 1.00 atm has a volume of 2.58 L. What volume will this gas occupy at 38.0C and 1.00 atm? T 1 = 15.0 o C V 1 = 2.58 LV 2 = ? T 2 = 38.0 o C P 1 = 1.00 atmP 2 = 1.00 atm V 1 = V 2 T 1 T 2 2.58 L 288K = V2V2 311K = 288K= 311K V 2 x 288K=802L*K V2V2 =2.79L

Bell Ringer 1. If the pressure on a gas is decreased by , how much larger will the volume become? 2. Which gases makes the most ideal gases real gases?

Cooling Curve Review

Gas Laws Lab

Bell Ringer Four identical balloons contain equal volumes of gas at STP. Balloon #1 contains H 2 gas Balloon #2 contains He gas Balloon #3 contains O 2 gas Balloon #4 contains N 2 gas A. Which balloon would weigh the most? Explain B. According to the KMT, why would the balloons expand upon heating?

DEMOS Pressure Cooker

Bell Ringer If you have a basketball that has a volume of 2.2L at a pressure of 3.00atm. What would its volume be at Standard Pressure?

1.As the temperature of a liquid increases, its vapor pressure A. IncreasesB. Decreases C. Remains the same 2.According to Reference Table H, what is the vapor pressure of propanone at 45C? 3.What is the name of the of the phase change that turns a solid directly into a gas? 4.Which liquid on Table H has the strongest intermolecular forces of attraction? A. Increases 70.0 kPa Sublimation Ethanoic Acid

Amadeo Avogadro created two important ideas used in science 1. Hypothesis If we have two gases with the same temperature and pressure at the same volume, they will have the same number of molecules. Gases are made of mostly empty space, so the size of the individual molecules does not matter Example - A sample of H 2(g) contains 1 x 10 23 molecules at a particular volume at STP. How many molecules of CO 2(g) takes up the same volume at STP? Same T, same P and same V= same # of molecules 1 x 10 23

2. Molar volume of a gas In chemistry, we use very large numbers of atoms. So Avagadro created a large unit called - Mole= 602,000,000,000,000,000,000,000 objects Pair = 2 Dozen = 12 Mole = 6.02 x 10 23 If we have one mole of ANY gas at standard temperature and pressure, it will take up of space Examples 1. How much room does 6.02 x 10 23 molecules of N 2(g) occupy at STP? One mole= 22.4 L 2. How much volume does 0.5 moles of CO 2(g) occupy at STP? 11.2L

3. If we have 3.01 x 10 23 molecules of CO 2(g) at STP, what is the volume? 0.5 moles11.2 L 4. How many molecules are in 44.8 L of H 2 S (g) at STP? 2 moles 2 x 6.02 x 10 23 1.204 x 10 24 5. If we have 9.03 x 10 23 molecules of a gas at STP, what is the volume? 1.5 moles33.6 L

Daltons Law of Partial Pressure

the total P of a mixture of gases is equal to the sum of partial P of component gases, no matter how many different gases P T = P 1 + P 2 + P 3 + Partial Pressure- P of each gas in mixture

Why? the particles of each gas in a mixture have an equal chance to hit the walls so each gas exerts P independent of that exerted by other gases total P is result of the total # of collisions per unit of wall area

Table H worksheet

Bell Ringer According to Reference Table H, which liquid will evaporate more rapidly? At what temperature does ethanol have the same vapor pressure as propanone at 68.5C?

Bell Ringer A gas sample has a volume of 25.0 ml at a pressure of 1.0 atm. If the new volume increases to 50.0 ml and the temperature remains constant, the new pressure will be?

a gas often changes in T, P, and V all at once the other gas laws can be combined into one law Combined Gas Law- relationship between P, V, and T of a fixed amount of gas

Example - A gas is collected at 273 K and 2.00 atm to a volume of 50.0 ml. What is the new pressure of a gas if the temperature drops to 200.0 K and the volume increases to 75.0 ml? 2.00 x 50 ml 273 K = P 2 x 75.0 ml 200.0 K 20,475 x P 2 20,000 P 2 = 0.97680 atm = T 1 = 273 K V 1 = 50 mL V 2 = 75.0 ml T 2 = 200.0 K 0.977 atm P 1 = 2.00 atm P 2 = ?

A Helium-filled balloon has volume of 50.0 L at 25C and 1.08 atm. What volume will it have at 0.855 atm and 10.C? (1.08 atm)(50.0 L) 298 K = (0.855 atm)(V 2 ) 283 K 254.79 x V 2 15282 V 2 = 59.9788 L = T 1 = 25C V 1 = 50.0 L V 2 = ? T 2 = 10.C 60. L P 1 = 1.08 atmP 2 = 0.855 atm = 298 K = 283 K

Bell Ringer Which 5.0 ml sample of NH 3 will take the shape of and completely fill a closed 100.0 ml container? A. NH 3(s) C. NH 3(g) B. NH 3(l) D. NH 3(aq)

Sub Gas Laws and Boyles Problems

Bell Ringer Which sample at STP has the same number of molecules as 5 liters of NO 2(g) at STP? A.5 grams of H 2(g) B.5 liters of CH 4(g) C.5 moles of O 2(g) D.5 x 10 23 molecules of CO 2(g)

a gas often changes in T, P, and V all at once the other gas laws can be combined into one law Combined Gas Law- relationship between P, V, and T of a fixed amount of gas

Example - A gas is collected at 273 K and 2.00 atm to a volume of 50.0 ml. What is the new pressure of a gas if the temperature drops to 200.0 K and the volume increases to 75.0 ml? 2.00 x 50 ml 273 K = P 2 x 75.0 ml 200.0 K 20,475 x P 2 20,000 P 2 = 0.97680 atm = T 1 = 273 K V 1 = 50 mL V 2 = 75.0 ml T 2 = 200.0 K 0.977 atm P 1 = 2.00 atm P 2 = ?

A Helium-filled balloon has volume of 50.0 L at 25C and 1.08 atm. What volume will it have at 0.855 atm and 10.C? (1.08 atm)(50.0 L) 298 K = (0.855 atm)(V 2 ) 283 K 254.79 x V 2 15282 V 2 = 59.9788 L = T 1 = 25C V 1 = 50.0 L V 2 = ? T 2 = 10.C 60. L P 1 = 1.08 atmP 2 = 0.855 atm = 298 K = 283 K

Bell Ringer A 1.00-mole sample of a neon gas occupies a volume of 22.4 liters @ 298K and 101.3 kPa. Calculate the density of this sample. 0.827 g/L

Bell Ringer Using Table H, how would you have to adjust your cooking time of pasta high in the mountains?

Water rapidly boiling on a stove

120 o C

Bell Ringer A gas occupies a volume of 560.ml at a temperature of 100.C. To what temperature must the gas be changed if it is to occupy 400.ml, with the pressure remaining unchanged?

Heating / Cooling Curve of Water 140 120 100 80 60 40 20 0 -20 Temperature ( o C) Heat added at a constant rate liquid water water and steam steam ice and water ice Heating Cooling

Bell Ringer What is the difference between the different states of matter? [in terms of energy or...

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