91Ó°ÊÓ

\(\mathrm{D}_{2} \mathrm{O}\) will have maximum density at: (a) \(20^{\circ} \mathrm{C}\) (b) \(9^{\circ} \mathrm{C}\) (c) \(11.5^{\circ} \mathrm{C}\) (d) \(15.5^{\circ} \mathrm{C}\)

Heavy water \(\left(\mathrm{D}_{2} \mathrm{O}\right)\) freezes at: (a) \(3.8^{\circ} \mathrm{C}\) (b) \(38^{\circ} \mathrm{C}\) (c) \(0^{\circ} \mathrm{C}\) (d) \(-3.8^{\circ} \mathrm{C}\)

Action of water or dilute mineral acids on metals can give: (a) Tritium (b) Dihydrogen (c) Trihydrogen (d) Mono hydrogen

Water is oxidized to oxygen by: (a) \(\mathrm{H}_{2} \mathrm{O}_{2}\) (b) \(\mathrm{KMnO}_{4}\) (c) \(\mathrm{ClO}_{2}\) (d) Fluorine

What is the formula of Calgon? (a) \(\mathrm{MgSO}_{4}\) (b) \(\mathrm{Na}_{3} \mathrm{PO}_{4}\) (c) \(\mathrm{Mg}_{3}\left(\mathrm{PO}_{4}\right)_{2}\) (d) \(\left(\mathrm{NaPO}_{3}\right)_{6}\)

The products formed when heavy water is reacted with magnesium nitride, are: (a) \(\mathrm{ND}_{3}, \mathrm{Mg}(\mathrm{OD})_{2}\) (b) \(\mathrm{ND}_{3}, \mathrm{Mg}(\mathrm{OH})_{2}\) (c) \(\mathrm{NH}_{3}, \mathrm{Mg}(\mathrm{OH})_{2}\) (d) \(\mathrm{NH}_{3}, \mathrm{Mg}(\mathrm{OD})_{2}\)

Reaction of potassium with water is: (a) Hydrolysis (b) Absorption (c) Exothermic (d) Endothermic

The reagent commonly used to determine hardness of water titrimetrically is: (a) Disodium salt of EDTA (b) Sodium thiosulphate (c) Sodium citrate (d) Oxalic acid

In the following compound \(\mathrm{H}\) is covalent bonded in case of: (a) \(\mathrm{CaH}_{2}\) (b) \(\mathrm{NaH}\) (c) \(\mathrm{SiH}_{4}\) (d) \(\mathrm{BaH}_{2}\)

In which of the following substances, hydrogen bonding is absent? (a) \(\mathrm{H}_{2} \mathrm{O}\) (b) HF (c) Salicylaldehyde (d) \(\mathrm{CCl}_{4}\)