NEET Practice Questions (MCQs) with Answers & Solutions

Hydrogen bonding occurs when hydrogen is bonded to highly electronegative atoms such as fluorine, oxygen, or nitrogen. Among the given options, HF (Hydrogen Fluoride) is the only compound where hydrogen is bonded to fluorine, which is highly electronegative. This leads to the presence of hydrogen bonding in HF.

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.

Spirit of salt is a common name for hydrochloric acid, which contains chlorine. The other options, such as Fisher salt (sodium thiosulfate), Epsom salt (magnesium sulfate), and Fremy's salt (potassium nitrosodisulfonate) do not contain chlorine.

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.

The effective component of bleaching powder (Ca(OCl)â‚‚) is chlorine (Cl). It is the chlorine that performs the bleaching action by undergoing a chemical reaction to form hypochlorous acid (HOCl), which is a strong oxidizing agent and responsible for the bleaching effect.

Fluorine ($F_2$) is prepared by the electrolytic method. The process involves the electrolysis of a solution of potassium fluoride (KF) in anhydrous hydrogen fluoride (HF) to produce fluorine gas at the anode.

Chlorine dioxide ( ext{ClO}_2) can be prepared by passing chlorine gas ( ext{Cl}_2) over hot silver chromate ( ext{Ag}_2 ext{CrO}_4). The reaction is as follows: ext{Cl}_2 + ext{Ag}_2 ext{CrO}_4 ightarrow ext{ClO}_2 + ext{AgCl} + ext{CrO}_2.

In aqueous solution, potassium chloride (KCl) reacts with perchloric acid (HClO_4) to form a white precipitate of potassium perchlorate (KClO_4). The reaction is as follows: ext{KCl} + ext{HClO}_4 ightarrow ext{KClO}_4 (white precipitate) + ext{HCl}.