A gas mixture contains 75.2% nitrogen and 24.8% krypton by mass. What is the partial pressure of krypton in the mixture if the total pressure is 853mmHg ?

Answer 1

Take a 100 g sample which gives you 75.2g N2 and 24.8g Kr.
mols N2 = grams/molar mass
mols Kr = grams/molar mass

Then X = mol fraction
XN2 = nH2/total mols
XKr = nKr/total mols

pN2 = XN2*total P
pKr = XKr*total P