Q 2. 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?
Hydrogen and oxygen combine in the ratio of 1:8 by mass to form water.
For every 1 g of Hydrogen, 8 g of oxygen is needed for the reaction to take place.
Therefore, for 3 g of Hydrogen, the mass of oxygen needed = 8 * 3 = 24 g.
Hence, 24 g of Oxygen is needed to complete reaction with 3 g of Hydrogen.