Question

A sample of H2SO4 contains 2.02 g of hydrogen, 32.07 g of sulfur, and 64.00 g of oxygen. How many grams of sulfur and grams of oxygen are present in a second sample of H2SO4 containing 7.27g if hydrogen

Answer 1

From the chemical formula of sulfuric acid, we can see the molar ratio:

H : S : O 
2 : 1 : 4

Now, we convert the mass of hydrogen given into the moles of hydrogen. This is done using

Moles = mass / Mr
Moles = 7.27 / 1
Moles = 7.27

Therefore, the moles will be:

S = 7.27 / 2 = 3.64 moles
O = 7.27 * 2 = 14.54 moles

Now, the respective masses are:
S = 32 * 3.64 = 116.48 grams
O = 16 * 14.54 = 232.64 grams