Chemistry 141 Name Martin LarterQuiz 4 (20 points) March 2, 2011Data: PV=nRT R = 62.4 L torr/mol K = 0.0821 L atm/mol K1. (5 points) A certain amount of gas at 25oC and at a pressure of 0.800 atm is contained in a glass vessel. Suppose that the vessel can withstand a pressure of 2.00 atm. How high can you raise the temperature of the gas without bursting the vessel?P1 = 0.800 atmP2 = 2.00 atmT1= 25oC = 298 KT2= ???P1V1n1T1=P2V2n2T2→→P1T1=P2T2→→ T2=T1(P2P1)T2=298 K(2.00 atm0.800 atm)=745 K∨472℃2. (5 points) Ozone molecules in the stratosphere absorb much of the harmful radiation from thesun. Typically, the temperature and pressure of ozone in the stratosphere are 250 K and 1.0 x 10-2 atm, respectively. How many ozone molecules are present in 1.0 L of air under these conditions?P = 1.0 x 10-2 atmT = 250 KV = 1.0 LR = 0.0821 L atm/mol KPV =nRT → →n=PVRT=(1.0 ×10−2atm)(1.0 L)mol K(0.0821 Latm) (250 K)¿4.9 ×10−4mol ozone? molecules ozone=4.9 ×10−4mol ozone×6.022× 1023molecules ozone1mol ozone¿2.9× 1020molecules ozone3. (5 points) Consider the formation of nitrogen dioxide from nitric oxide and oxygen:2 NO(g) + O2(g) 2 NO2(g)If 9.0 L of NO are reacted with excess O2 at STP, what is the volume in liters of the NO2 produced?? L NO2=9.0 L NO ×2 L NO22 L NO=9.0 L NO24. (5 points)Calculate the density of hydrogen bromide (HBr) gas in grams per liter at 733 mmHg and 46oC.P = 733 torrT = 46oC = 319 KR = 62.4 L torr/mol KPV =nR T → →nV=PRT=(733 torr)mol K(62.4 L torr) (319 K)=3.68× 10−2mol HBr1 L? g HBrL=g HBrmol HBr×mol HBrL HBr=80.91 g HBr1 mol HBr×3.68 ×10−2mol HBr1 L¿2.97 g HBrLAlternative Method (If you remembered formula)d=(MW × P)(R ×T )=(80.91gmol)×733 torr(62.4L× torrmol × K)×319 K=2.98 g
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