Chemical Reacti...

When hydrogen sulphide gas is passed through a blue solution of copper sulphate, a black precipitate of copper sulphide is obtained and the sulphuric acid so formed remains in the solution. The reaction is an example of:

Complete the chemical reaction $$Mg(s)+H_2SO_4(aq)\rightarrow$$? 

$$Lead\ Sulphate + Ammonium\ Hydroxide \rightarrow Ammonium\ Sulphate + Lead\ Hydroxide$$

Identify the following reactions as endothermic or exothermic.
(i) $$2NaHCO_3+  \text{energy}\longrightarrow Na_2CO_3+H_2O+CO_2$$
(ii) $$2Mg+O_2\longrightarrow 2MgO+\text{energy}$$

Balance the equation by providing the missing coefficients.
$$.. C_2H_4(g)\quad+\quad  ..O_2(g)\longrightarrow \quad.. CO_2(g)\quad+\quad.. H_2O(g)$$

$$xFe+S\rightarrow FeS\\ FeS+2HCl\rightarrow { FeCl }_{ y }+{ H }_{ 2 }S$$
Find the value of x and y.

Differentiate between an exothermic and an endothermic reaction.

What type of chemical reaction is it?

On passing excess $$CO_2$$ in aqueous solution of sodium carbonate, the substance obtained is :

(i) Reaction between calcium oxide and water is a ...... reaction.
(ii) Action of strong heat on mercuric oxide is a ...... reaction.