Amongst the following,the form of water with the lowest ionic conductance at $298 \ K$ is

Which of the following salts contains interstitial water molecules?

Permanent hardness in water cannot be cured by

How is heavy water prepared? Compare its physical properties with those of ordinary water.

Select the correct statement about water.
$(i)$ Critical temperature of $H_2O$ is less than $NH_3$.
$(ii)$ Standard boiling point of water is $100 \ ^oC$.
$(iii)$ Critical volume of $H_2O$ is less than $NH_3$.

What is true about ice?