a. Magnesium Burns in oxygen.
--β©it produces light bright enough to blind you temporarily.
b. Calcium carbonate is heated.
--β© form calcium oxide and evolve carbon dioxide gas.
c. Hydrogen reacts with nitrogen at necessary condition.
----β©some of the hydrogen and nitrogen will react to form ammonia.
d. potassium hydroxide reacts with nitric acid.
---β©When potassium reacts with nitric acid then, potassium displace hydrogen from its solution and becomes colorless liquid.
e. Carbon dioxide is treated with limewater.
---β©to form a white precipitate (appears milky) of calcium carbonate, CaCO 3.
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