Question

What do you observe when manganese oxide is treated with concentrated hydrochloric acid?

Answer 1

Answer:

Greenish yellow gas is evolved

Explanation:

When manganese dioxide reacts with conc. Hcl it gives off chlorine gas and leaves behind a dense mass black oxide

Answer 2

All the oxides and hydroxides of metals are basic in nature.

Magnesium oxide is also basic in nature and is a water insoluble base.

When a dilute acid reacts with a base it forms salt and water because the acidity and basicity of the acid and base respectively neutralise each other.This process is known as neutralisation reaction.

When MgO reacts with HCl it forms MgCl2 and water.

In equation form

MgO + 2HCl — MgCl2 + H2O