Question

Explain the statement metal oxides are of basic nature.

Answer 1

Hint: If any substance reacts with acid and it forms salt and water, then the substance is basic in nature and if any substance reacts with a base and it forms salt and water, then the substance is acidic in nature.

Complete answer:
A substance can be differentiated as acid or base on the basis of pH meter, i.e., if the substance has a pH between 0 – 6.9 then, it is an acid and if the substance has a pH between 7.1 – 14 then, it is a base.
If any substance reacts with acid and it forms salt and water, then the substance is basic in nature and if any substance reacts with a base and it forms salt and water, then the substance is acidic in nature.
Metal oxides are compounds in which there are two elements, i.e., a metal and an oxygen atom. For example, sodium oxide ($N{a}_{2}O$), magnesium oxide ($MgO$), Calcium oxide ($CaO$), etc. These are basic because when they react with dilute acids then, they form salt and water which show that metal oxides are basic.
This can be seen in this reaction:
$2HCl+MgO\to MgC{l}_2+H_{2}O$
There is another reason which can tell the metal oxides are basic in nature is that when they are treated with water then they produce metal hydroxides which are strong bases and in water they are always in hydroxyl ions.

Note:
When the solution of metal oxide is tested for the litmus paper test then it will turn the red litmus paper to blue because of its basic nature. When the solution of non-metallic oxide is treated with litmus paper then it will turn blue litmus paper to red.