Question

Identify the correct statements from the following.
(i) The number of hydrogen bonded water molecules in copper sulphate pentahydrate is one.
(ii) Lanthanum and zirconium form non-stoichiometric hydrides.
(iii) In solid form of $H _{2} O$, each oxygen is surrounded by six oxygen in octahedral positions at a distance of $276\, pm$.

• A. i, ii, iii
• B. i, ii
• C. ii, iii
• D. i, iii

Answer 1

Answer: (B)

Both (i) and (ii) statements are correct.

The number of hydrogen bonded water molecules in copper sulphate pentahydrate is one



Water of crystallisation $\left[ Cu \left( H _{2} O \right)_{4}\right] SO _{4} \cdot H _{2} O$

lanthanum and zirconium form non-stoichiometric hydrides. Some hydrides are $LaH _{2}, LaH _{3}, ZrH _{2} $. All hydrides are non-stoichiometric with variable composition, e.g. $\operatorname{ZrH}_{x}(1.30 \leq x \leq 1.75) .$ Most of these hydrides are good conductors of electricity in solid state. In solid form of $H _{2} O$, each oxygen atom is bonded to four hydrogen atoms, two by hydrogen atoms and two by normal covalent bonds in a near tetrahedral configuration.