How many grams are in 0.334 moles of HCl (hydrochloric acid)?

The reaction of ammonium perchlorate with itself is as follows:
2NH4ClO4 > N2 + Cl2 + 2O2 + 4H2O 

From the periodic table:
molecular weight of nitrogen = 14 grams
molecular weight of oxygen = 16 grams
molecular weight of hydrogen = 1 gram
molecular weight of chlorine = 35.5 grams

Therefore:
molar mass of ammonium perchlorate =  117.5 grams

Now, we know that 2 x  117.5 = 235 grams of ammonium perchlorate are required to produce 28 grams of nitrogen. We can use cross multiplication to determine the amount of hydrogen produced from 3.1 grams of ammonium perchlorate as follows:
mass of nitrogen = (3.1 x 28) / 235 = 0.369 grams