Which of the following statement is correct ?

Options

A. Shine of freshly cut sodium is due to strong metallic bonding
B. `Rb_(2)CO_(3)` decomposes readily on heating to `RbO` and `CO_(2)`.
C. Among hydroxides of alkali metals, `LiOH` is least soluble whereas `CsOH` is highly soluble in water.
D. White metal is an alloy of lithium with zinc.

Answer

3

Explanation

`(1)` It is due to oscillations of free `//` mobile electrons.
`(2) Rb_(2)CO_(3)` does not decomposes as it has very which thermally stability smongst the alkali metal carbonates on account of the fact that higger cation stabilises the bigger anion through crystal lattice effect.
`(3)` Down the alkali metal group, the solubility of the hydroxides increases as there is more decrease in lattice energy as compared to that of hydration energy.
The order is thus, `CsOHgtRbOHgtKOHgtNaOHgtLiOH`.
`(4)` White metal is an alloy of lithium with lead.