Chemical Reaction

In the thermal decomposition reactions, the compound decomposes by heat into its ....................

• simple components

• primary elements

• other compounds

• all the previous answers

When we heat mercuric oxide, we get .................

• mercuric oxide and water

• mercuric oxide and oxygen

• mercury and hydrogen

• mercury and oxygen

When copper hydroxide is heated, we obtain ....................

• copper carbonate and water

• copper oxide and water

• copper oxide and hydrogen

• copper and hydrogen

When calcium carbonate is heated, ................ are obtained.

• calcium bicarbonate and carbon dioxide

• calcium hydroxide and carbon dioxide

• calcium oxide and carbon monoxide

• calcium oxide and carbon dioxide

On heating copper carbonate, its color changes from ................

• blue to black

• green to black

• black to green

• green to blue

Most metal sulphates decompose when they heated to metal oxide and ............ gas.

• CO2

• O2

• SO2

• SO3

On heating copper sulphate, a .......... precipitate is formed.

• black

• green

• blue

• red

Chemical reaction is a process of breaking up bonds between molecules of reactants and formation of new bonds between molecules of products.

• True

• False

Copper sulphate is decomposed by heat into black copper oxide and sulphur dioxide gas.

• True

• False