Question

Complete the reaction and then balance.

Barium chloride+ Sodium sulphate $\to$……….. +………………….

Answer 1

• When Barium chloride react with Sodium sulphate, Barium sulphate and Sodium chloride.
• Barium chloride + Sodium sulphate $\to$Barium sulphate + Sodium chloride.
• This is an example of double decomposition reaction, because the products obtained by mutual exchange of Na⁺ and Ba²⁺ ions.
• Here Barium sulphate is precipitated. So this is also an example for precipitation reaction.

Definition of Double decomposition

It is a type of decomposition reaction in which products obtained by interchanging the ions of reactants. Usually a solid is obtained as its one of the product. So this reaction is also called precipitation reaction.

To balance the chemical equation following methods are used.

Step 1

Write the skeletal equation.

${\mathrm{BaCl}}_2+{\mathrm{Na}}_2{\mathrm{SO}}_4\to {\mathrm{BaSO}}_4+\mathrm{NaCl}$

Step 2

To equalize Sodium, multiply NaCl by 2

${\mathrm{BaCl}}_2\left(\mathrm{aq}\right)+{\mathrm{Na}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)\to {\mathrm{BaSO}}_4\left(\mathrm{s}\right)+2\mathrm{NaCl}\left(\mathrm{aq}\right)$

Now the equation is balanced.