Question

The correct option(s) regarding borax is/are :

• A. White crystalline solid
• B. More soluble in cold water
• C. Less soluble in hot water
• D. More soluble in hot water

Answer 1

Answer: (A), (D)

More soluble in hot water

Borax is a white crystalline solid.
It is less soluble in cold water but more soluble in hot water.
Hence correct options are a and d.

THEORY
Properties:
Borax is a white crystalline solid.
1. It is less soluble in cold water but more soluble in hot water.
2. Its aqueous solution is alkaline.
$N{a}_2{B}_4{O}_7+7H_{2}O\to 4H_{3}B{O}_3+2NaOH$
3. Effect of heating: It first swells due to loss of water in the form of steam
$N{a}_2{B}_4{O}_7.10H_{2}O\stackrel{△}{\to }N{a}_2{B}_4{O}_7+10H_{2}O$
$N{a}_2{B}_4{O}_7\stackrel{△}{\to }2NaB{O}_2+B_2{O}_3\text{Sodium metaborate}$