Question

What is the colour of the precipitate formed when aqueous solution of sodium sulphate and barium chloride are mixed ?

• A. Yellow
• B. Green
• C. Orange
• D. White

Answer 1

Answer:

D. White

The colour of the precipitate formed is white.

When an aqueous solution of sodium sulphate ($\text{Na}_2\text{SO}_4$) is mixed with barium chloride ($\text{BaCl}_2$), a double displacement reaction takes place. Barium ions combine with sulphate ions to form an insoluble white precipitate of barium sulphate ($\text{BaSO}_4$).

The Chemical Equation:

$\text{Na}_2\text{SO}_4\text{ (aq)} + \text{BaCl}_2\text{ (aq)} \rightarrow \text{BaSO}_4\text{ (s)} \downarrow \text{ (White ppt)} + 2\text{NaCl (aq)}$