Calcium carbide + heavy water $\to$ ?
The product of the above reaction is

An inorganic salt $(A)$ is decomposed on heating to give two products $(B)$ and $(C)$. Compound $(C)$ is a liquid at room temperature and is neutral to litmus,while the compound $(B)$ is a colourless neutral gas. Compounds $(A)$,$(B)$ and $(C)$ are:

Which of the following can effectively remove all types of hardness of water?

Which can be used to prepare pure and demineralised $H_2O$ ?

Explain the importance of water for living organisms.

Assertion $(A)$ : $NaCl$ is less soluble in heavy water than in ordinary water.
Reason $(R)$ : Dielectric constant of ordinary water is more than that of heavy water.
The correct answer is