Question

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

Answer 1

Question :-

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

Solution :-

We know hydrogen and water mix in the ratio 1: 8.

For every 1g of hydrogen, it is 8g of oxygen.

Therefore, for 3g of hydrogen, the quantity of oxygen = 3 x 8 = 24g

Hence, 24g of oxygen would be required for the complete reaction with 3g of hydrogen gas.

Answer 2

The law of constant proportions states that in a chemical substance, the elements are always present in definite proportions by mass.

Hydrogen and oxygen combine in the ratio of 1:8 by mass to form water.

1 g of hydrogen reacts with oxygen = 8g

So in order to form water,

$\red\longrightarrow$ 3 x 8 = 24 g of oxygen will react completely with 3g of hydrogen gas.