Question

Methane is a compound which is 75% carbon, by mass, the balance being hydrogen. If a sample of methane weighs 24 g, what mass of hydrogen does it contain?

Answer 1

The mass  of hydrogen  is 6 grams

calculation

step 1: find the % of hydrogen

= total %(100) - % of carbon (75%)

= 100- 75 =25%

step2: find the mass of hydrogen  from its %

that is 25/100 of 24 grams = 6 grams