Which of the following substances has covalent bonding?

Covalent bond length of a chlorine molecule is $1.98 \mathring{A}$. Covalent radius (in $\mathring{A}$) of chlorine atom is $........$

The bond between two identical non-metallic atoms contains electrons that are:

Draw the Lewis structures for the following molecules and ions:
$H_2S, SiCl_4, BeF_2, CO_3^{2-}, HCOOH$

The electronic configurations of four elements are given below:
$(I) \, 1s^2 \, (II) \, 1s^2 2s^2 2p^2 \, (III) \, 1s^2 2s^2 2p^5 \, (IV) \, 1s^2 2s^2 2p^6$
Which element has the ability to form both ionic and covalent bonds?

Which of the following has the least covalent $P-H$ bond?