CHM 1045 Fall 2008
Quiz 7
Name (print)___________________
Show your work for complete (and partial) credit. Report your answers to the correct
number of significant figures, and use units where appropriate.
PA = XAPtot XA = nA/ntot 760mm Hg = 1atm. K=°C+273.15 R=0.082058L.atm.mol-1.K-1
1. A gas sample consists of a mixture of 0.33mol of N2(g) and 0.25mol H2(g). What
would be the total volume of the mixture at 25°C and 0.75atm?
2. What is Charles' Law (the relationship between temperature and volume)? State the
law with words or as a mathematical equation. What conditions, if any, are required
for Charles' Law to be valid?
3. A gas sample with a volume of 1.75L and a pressure of 710.mmHg at 25°C has its
volume reduced to 1.50L and its temperature decreased to 20.°C. What is the
resulting pressure?
4. The density of a gas sample at 105°C and 1.00atm. is 1.564g/L.
a) Calculate either the number of moles in 1.00L or the volume of 1.00mol of the gas.
b) Calculate the molecular weight of the gas.
extra credit: In a mixture of gasses, the mole fraction of nitrogen is 0.55 and the partial
pressure of nitrogen is 800.mmHg. What is the partial pressure of all other
components of the mixture?