Identify the correct statements about alkali metals.

A. The order of standard reduction potential $({\mathrm{M}}^{+} | \mathrm{M})$ for alkali metal ions is $\mathrm{Na} > \mathrm{Rb} > \mathrm{Li}$.

B. $\mathrm{CsI}$ is highly soluble in water.

C. Lithium carbonate is highly stable to heat.

D. Potassium dissolved in concentrated liquid ammonia is blue and paramagnetic.

E. All alkali metal hydrides are ionic solids.

Choose the correct answer from the options given below

A. Electrode potential of given elements are:

 $$\begin{gathered} \mathrm{Li} = -3.04 \\ \mathrm{Na} = -2.714 \\ \mathrm{Rb} = -2.98 \end{gathered}$$

The standard reduction potentials (E) of the alkali metals do not follow the trend based on ionisation energies. Unexpectedly, lithium is the strongest reductant, and sodium is the weakest. Therefore, reducing character sequences is $\mathrm{Na} <\mathrm{Rb} < \mathrm{Li}.$

B. The low solubility of $\mathrm{CsI}$ is due to smaller hydration enthalpy of its two ions.

C. ${\mathrm{Li}}_2{\mathrm{CO}}_3$ decomposes readily to lithium monoxide and carbon dioxide.

D. Alkali metals are sodium, potassium which with liquid ammonia produce blue coloured solutions. Alkali metals dissolve in liquid ammonia to produce ammoniated electrons. It is paramagnetic due to the presence of unpaired electrons.

E.All the alkali metal hydrides are ionic solids with high melting points.

Hence, the correct option is A and E