If the electron pair forming a bond between two atoms $A$ and $B$ is not in the centre,then the bond is

Which of the following molecules will show a dipole moment?

Elements $X, Y$ and $Z$ have $4, 5$ and $7$ valence electrons respectively.
$(a)$ Write the molecular formula of the compounds formed by these elements individually with hydrogen.
$(b)$ Which of these compounds will have the highest dipole moment?

Which compound among the following will have a permanent dipole moment?

Which of the following compounds is non-polar?

Assertion : Molecules of larger size have higher polarizability.
Reason : Polarizability is observed only in those molecules which have a permanent dipole moment.