Question

Give an example of a combination reaction between two elements.

Answer 1

Combination reaction:-

1. A combination reaction is a type of reaction in which two or more elements or compounds (reactants) combine to form a single compound (product).
2. This reaction involves the formation of new bonds and along with the products that are formed a large amount of energy is also generated in form of heat.
3. Example: $\underset{\mathrm{Nitrogen}\mathrm{gas}}{{\mathrm{N}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Hydrogen}\mathrm{gas}}{3{\mathrm{H}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Ammonia}}{2{\mathrm{NH}}_3\left(\mathrm{g}\right)}$

The reaction of Calcium oxide and Silicon (IV) oxide:-

1. Here calcium oxide $\left(\mathrm{CaO}\right)$ also known as quick lime reacts with silicon (IV) oxide$\left({\mathrm{SiO}}_2\right)$ also known as silica at a temperature of $1100°C-1200°C$
2. This reaction forms a salt of calcium silicate $\left({\mathrm{CaSiO}}_3\right)$.
3. The balanced reaction is as follows: $\underset{\mathrm{Calcium}\mathrm{oxide}}{\mathrm{CaO}\left(\mathrm{aq}\right)}+\underset{\mathrm{Silicon}\left(\mathrm{IV}\right)\mathrm{oxide}}{{\mathrm{SiO}}_2\left(\mathrm{aq}\right)}\stackrel{(1100-1200)°\mathrm{C}}{\to }\underset{\mathrm{Calcium}\mathrm{silicate}}{{\mathrm{CaSiO}}_3\left(\mathrm{aq}\right)}$
4. Hence this reaction is also known as a combination reaction.

Therefore, the reaction of calcium oxide and silicon (IV) oxide forms calcium silicate $\left({\mathrm{CaSiO}}_3\right)$ and the reaction is a combination reaction.