Question

The pair of compounds which cannot exist together in aqueous solution is:

• A. $N{a}_{2}C{O}_3$ and $NaHC{O}_3$
• B. $NaHC{O}_3$and $NaOH$
• C. $NaOH$ and $Na{H}_{2}P{O}_4$
• D. Both (B) and (C)

Answer 1

The correct option is D Both (B) and (C)

Sodium bicarbonate and sodium hydroxide cannot exist together in the aqueous solution because they react with each other. Sodium bicarbonate acts like an acid and sodium hydroxide acts as a base. The products of the reaction are sodium carbonate and water.

$NaHC{O}_3+NaOH\to N{a}_{2}C{O}_3+H_{2}O$

Similarly, sodium hydroxide and sodium dihydrogen phosphate react to form sodium phosphate and water.

$Na{H}_{2}P{O}_4+2NaOH\to N{a}_{3}P{O}_4+2H_{2}O$

Hence, option D is correct.