Question

Magnesium burns in air with a dazzling white light and forms a white powder. What will be the action of aqueous solution of this powder on red litmus paper?
a. The red litmus paper will turn blue
b. The red litmus paper will turn violet
c. The red litmus paper will turn black
d. No change will occur on the red litmus paper​

Answer 1

magnesium oxide

Oxygen and magnesium combine in a chemical reaction to form this compound. After it burns, it forms a white powder of the magnesium oxide. Magnesium gives up two electrons to oxygen atoms to form this powdery product. This is an exothermic reaction.

Answer 2

The action of aqueous solution of this powder on red litmus paper is a. The red litmus paper will turn blue

• As we know metals form basic oxides. Magnesium being a metal forms basic oxide 'MgO' on burning in air to form of white powder.
• The basic solution of MgO powder is then tested with red litmus paper.
• Red litmus paper on action with a base always turns blue .
• Hence, when we apply the red litmus paper on MgO powder solution it turns blue . This indicates the presence of metal oxide or basic oxide.
• Hence, option a is correct answer.