The $H_2SO_4$ molecule contains .......

The most stable Lewis acid-base adduct among the following is

What is common between $NH_3$ and $PH_3$?

Which of the following molecules does not contain a coordinate bond?

In $BF_3$,the $B-F$ bond length is $1.3 \ \mathring{A}$. When $BF_3$ reacts with $Me_3N$,it forms an adduct $Me_3N \to BF_3$. In this adduct,the $B-F$ bond length will be ..........

Solid $CuSO_4 \cdot 5H_2O$ has covalent,ionic,as well as coordinate bonds. The copper atom/ion forms $.........$ coordinate bonds with water molecules.