When a lot of dry powder of a substance X is released over a fire, the fire gets extinguished.
(a) Name the substance X.
(b) How does this substance extinguish the fire ?
(c) Name another susbtance which behaves like X.
(a) Sodium hydrogen carbonate.
(b) The heat of fire decomposes sodium bicarbonate to produce carbon dioxide gas. This carbon dioxide covers the fire like a blanket and cuts off supply of air to the burning substance. Due to this the fire gets extinguished.
(c) Potassium hydrogen carbonate.