Identify the correct statement regarding geometry and lone pair of electrons present in $\mathrm{CH}_4$ and $\mathrm{SiCl}_4$.

What type of hybridisation is present in square planar geometry of complex $\left[\mathrm{Ni}(\mathrm{CN})_4\right]^{2-}$

What are the different types of bonds formed by sulphur with oxygen in thiosulfuric acid?

Which of the following is not an alkali metal?