Chemistry MCQs for NEET — Practice Questions with Answers

The bonding in HCl is polar covalent. This is because chlorine (Cl) is more electronegative than hydrogen (H), resulting in an unequal sharing of electrons. This creates a dipole moment, with a partial negative charge on the chlorine atom and a partial positive charge on the hydrogen atom.

The bond dissociation energy decreases down the group in halogens. This is because the atomic size increases, leading to a longer bond length and weaker bond strength. Therefore, the correct order of bond dissociation energy should be $ I_2 extgreater Br_2 extgreater Cl_2 extgreater F_2 $. Hence, the order given in option o2 is not proper.

The melting point of an ionic compound is largely determined by the strength of the ionic bonds holding the lattice together. Among the given options (NaF, NaCl, NaBr, NaI), NaF has the highest melting point because it has the maximum ionic character. This is due to the high electronegativity of fluorine which leads to a strong electrostatic attraction between the sodium and fluoride ions, resulting in a high melting point.

$BCl_3$ (Boron trichloride) can form a dative bond with ammonia ($NH_3$) because boron has an incomplete octet and can accept a pair of electrons from the nitrogen atom in ammonia.

Fluorine does not show higher oxidation states because it lacks d-orbitals. All other halogens can utilize their d-orbitals to achieve higher oxidation states, but fluorine, being in the second period, has no d-orbitals available. Therefore, the correct answer is 'It has no d-orbital'.

The molecule $OF_4$ is theoretically not possible. Oxygen cannot form four bonds with fluorine due to its inability to expand its octet. Oxygen can form a maximum of two bonds in stable compounds. Therefore, the correct answer is $OF_4$.

HF is liq. Because of int . molec. H - Bond

$ 3HOCl^{(+1)} \rightarrow 2HCl^{(-1)} + HCl^{(+5)}O $

$ 3HCl + HNO_3 \rightarrow NOCl + 2H_2O + Cl_2 $