In which of the following, all bonds are not equivalent?

Write the Lewis dot structures of the following:

${\mathrm{H}}_2{\mathrm{SO}}_4$

In each of the following pairs, select the species having the greater stabilization:

${\mathrm{HNO}}_3$ and ${\mathrm{NO}}_3^{-}$.

In an ionic bond, the cation tends to polarise the electron cloud of the anion by pulling electron density towards itself. This causes development of covalent character in the ionic bond because the electron density gets localized in between the nuclei. The tendency of the cation to bring about the polarization of the anion is expressed as its polarising power. The ability of ion to undergo polarization is called its polarisability.

Dative bond is present in:

The percentage ionic character of a single bond may be estimated from ratio of the observed dipole moment to the calculated moment, assuming oppositely charged ions located at a distance equal to the bond length. The observed dipole moments of $\mathrm{HCl}, \mathrm{HBr}$ and $\mathrm{HI}$ are $1.03, 0.79$ and $0.38 \mathrm{D}$, respectively. Calculate the percentage ionic character of the bond in each of these compounds. Do the results obtained are parallel to the magnitudes of the extra ionic resonance energies, $\mathrm{\delta }$, for these molecules?

(Given, then ${\mathrm{d}}_{\mathrm{H}-\mathrm{Cl}}=1·27\stackrel{\circ }{\mathrm{A}}, {\mathrm{d}}_{\mathrm{H}-\mathrm{Br}}=1·42 \stackrel{\circ }{\mathrm{A}}, {\mathrm{d}}_{\mathrm{H}-\mathrm{I}}=1.61 \stackrel{\circ }{\mathrm{A}}$).

Arrange the following compounds in decreasing order of dipole moment values. Explain the order.

$\left(\mathrm{a}\right){\mathrm{CCl}}_4 \left(\mathrm{b}\right){\mathrm{CHCl}}_3 \left(\mathrm{c}\right){\mathrm{CH}}_2{\mathrm{Cl}}_2 \left(\mathrm{d}\right){\mathrm{CH}}_3\mathrm{Cl}$

Arrange the following compounds in decreasing order of dipole moment values. Explain the order.

$\left(\mathrm{a}\right){\mathrm{CCl}}_4 \left(\mathrm{b}\right){\mathrm{CHCl}}_3 \left(\mathrm{c}\right){\mathrm{CH}}_2{\mathrm{Cl}}_2 \left(\mathrm{d}\right){\mathrm{CH}}_3\mathrm{Cl}$