Question

The ash which is collected after burning of magnesium ribbon is dissolved in water to give a solution X. What is the nature of the solution X when it is tested with indicators?

• A. It turns blue litmus red and phenolphthalein pink, hence it is an acidic solution.
• B. It turns red litmus blue and phenolphthalein pink, hence it is an basic solution.
• C. It turns blue litmus red and gives no colour with phenolphthalein, hence it is an acidic solution.
• D. It does not change colour of red or blue litmus and phenolphthalein, hence it is a neutral solution.

Answer 1

Answer: (B), (D)

The correct options are
B It turns red litmus blue and phenolphthalein pink, hence it is an basic solution.
D It does not change colour of red or blue litmus and phenolphthalein, hence it is a neutral solution.

$Mg+O_2\to MgO$
Magnesium Oxygen Magnesium
oxide (ash)
$MgO+H_{2}O\to Mg(OH{)}_2$
Magnesium Water Magnesium
hydroxide
(X)
$MgO+H_{2}O\to Mg(OH{)}_2$
Magnesium Water Magnesium
oxide hydroxide
(X)
Mg(OH)_2 solution is basic in nature which turns red litmus blue and phenolphthalein pink.