Question

Hydrogen and Oxygen combine in the ratio of 1:8 by mass to form water. What mass of oxygen would be required to react completely with 3 g of hydrogen gas?

Answer 1

Chemical formula of water is H₂O i.e.; 2 atoms of Hydrogen (H) combine with 1 atom of Oxygen (O) is used to make a molecule of water.

Hydrogen and Oxygen combine in the ratio = 1:8 by mass (Given)

i.e.; amount of Oxygen is 8 times the weight of Hydrogen gas

If mass of Hydrogen gas (H₂) given= 3 g,

and Oxygen is 8 times the weight of hydrogen (according to ratio)

then, the Oxygen is 3 ×8= 24 g