$A$ sample of water contains sodium chloride. It is:

Which pairs of ions are responsible for hardness of water?

When the first element of the periodic table is treated with dioxygen,it gives a compound whose solid state floats on its liquid state. This compound has an ability to act as an acid as well as a base. What products will be formed when this compound undergoes autoionisation?

Identify the incorrect statement regarding heavy water $(D_2O)$.

Why is water used as a medium for chemical reactions?

Which of the following statements does not define the characteristic property of water,"Water is a universal solvent"?