Chapter 13 Review

Chapter 13 ReviewUse the relationship between pressure, temperature, and volume to answer questionsPressure increases then volume decreases temperature is constantPressure decreases then volume increases temperature is constantVolume increases then temperature increases pressure is constantVolume decreases when temperature decreases pressure is constantFind the density of 1.0 L of nitrogen at STP (d = PM/RT)d = (1atm)(28 g/mol)(.0821 atm g/mol K)(273 K)

Answer: 1.24 g/LFind the density of methane CH4 at a pressure of 115 kPa and 45C. (d=PM/RT)Need to change kPa to atm first 115 kPa x 1atm = 1.13 atm 101.325

d = PM/RT

d= (1.13 atm) (16 g) (.0821)(318K)

Remember to change temperature to KelvinsAn 0.15 cm3 oxygen bubble is released from a diver at a pressure of 186 kPa and a temperature of 6C. What volume will this bubble have at the surface where the temperature is 13C and a pressure of 1 atm?Combine both Charles and Boyles Laws and change kPa to atm because units of atm must be the same186 kPa x 1atm 101.325 P1 V1 = P2 V2 (1.84 atm)(.15 cm3 ) = (1 atm) V T1 T2279 286Answer: .26 cm3A helium balloon will burst above 4 Liters. If it is partially filled (3.4 L) at a temperature of 26C. If pressure is constant, at what maximum temperature can the balloon be heated to before it bursts?V1 = V2 T1T2

3.4 L = 4L299 T2

Answer: 351.8 Kelvins 78.8CWhy would it be important for an anesthesiologist to know about gas laws to prevent injury to patients?Anesthesiologist needs to control temperature and pressure to not hurt or kill the patientThe barometer reads 756 mmHg, what is the atmospheric pressure in kPa?756 mmHg x 1atm x 101.325 kPa 760 mmHg 1 atm

Answer: 100.79 kPaCylinder of nitrogen gas is left in the sun; the temperature reaches 53C. The cylinder has a volume of 15-L and contains 158 g of nitrogen. What is the pressure in atmospheres inside the cylinder?PV = nRTn = m/MCombine both equations to get PV = mRT MP(15) = 158g(.0821)(326) =10.01 atm 28 g/molGas manometer has a pressure of 745 mmHg. Height of mercury is 9 mmHg higher on open end, what is the atmospheric pressure in atm?745 mmHg 9 mmHg = 736 mmHg

736 mmHg x 1 atm 760 mmHg

Answer: .968 atmStandard temperature273 KStandard pressureIn atm = 1 atm

In mmHg = 760 mmHg

In Pa = 101325 Pa

In kPa = 101.325 kPaOne mole of gas has a volume of ___ at STP22.4 LA rising barometer means that atmospheric pressure is increasingA falling barometer means that atmospheric pressure is decreasingIdeal gas constant has a value of _____ in atm.0821 atm-L/mol-KFind the volume of gases at STP gasses are given in gramsMolar volume of any gas at STP is 22.4 L

Methane CH4 32 grams 32/16 = 2 x 22.4 L = 44.8 L16 is the molar mass of methaneWater vapor 36 grams 36/18 = 2 x 22.4 L = 44.8 L18 is the molar mass of waterNeon 50 grams 50/20 = 2.5 x 22.4 L = 56 L20 is the molar mass of neonStatements about ideal gasMolecules have elastic collisions

Energy remains the same

Has mass

Exerts pressureIdeal gas law cannot predict behavior of a real gas atLow temperatures and high pressure

Pressure Pressure = Force/areaBoyles LawAt constant temperature, pressure and volume are inversely proportionalCharles LawAt constant pressure, temperature and volume are directly proportionalTo use a manometer you need toMeasure the difference in height of two mercury columns

Relationship between volume and number of moles of a gasIf volume increases so does the number of moles