Question

An environmental chemist sampling industrial exhaust gases from a coal-burning plant collects a CO2−SO2−H2O mixture in a 21.0−L steel tank until the pressure reaches 891.4 torr at 57.0°C. (a) How many moles of gas are collected? ____ mol gas (b) If the SO2 concentration in the mixture is 2.95 × 103 parts per million by volume (ppmv), what is its partial pressure? [Hint: ppmv = (volume of component/volume of mixture) × 106.] ____ torr

Answer 1

a)

pressure = 891.4 torr = 1.173 atm

volume = 21.0 L

temperature = 57 oC = 330.15 K

P V = n R T

1.173 x 21 = n x 0.0821 x 330.15

n = 0.9807

moles of gas = 0.909 mol

b)

concentration = 2.95 x 10^3 ppmv

parital pressure = (2.95 x 10^3 / 10^6 ) x 891.4

                         = 2.63 torr

                     

Answer 2