Question

How many grams of oxygen gas contains the same number of molecules as 16g of sulphur dioxide gas. (Oxygen-16u,Sulphur-32)

Answer 1

We know that equal moles of all gases contain equal number of molecules
1 mole sulphur = 32 + 2 x 16 = 64g
16g of sulphur = ----moles?
= 1/64 X 16 =1/4 mole
¼ mole of sulphur dioxide will have the same number of molecules as ¼ moles of oxygen
1 mole oxygen = 32 g
¼ moles oxygen = ----?
= ¼ x 32 = 8g
∴ 8 g of oxygen gas contain the same number of molecules as 16grams of sulphur dioxide gas.