Sodium carbonate is manufactured by the Solvay process. The products that are recycled are:

The reaction of an element $A$ with water produces a combustible gas $B$ and an aqueous solution of $C.$ When another substance $D$ reacts with this solution $C,$ it also produces the same gas $B.$ $D$ also produces the same gas even on reaction with dilute $H_2SO_4$ at room temperature. Element $A$ imparts a golden yellow color to the Bunsen flame. Then,$A, B, C,$ and $D$ may be identified as:

What is zeolite among the following?

The commercial method of preparation of potassium by reduction of molten $KCl$ with metallic sodium at $850 ^\circ C$ is based on the fact that:

Both lithium and magnesium display several similar properties due to the diagonal relationship; however,the one which is incorrect is:

Which one of the following dissolves in hot concentrated $NaOH$ solution?