The lightest gas is :

(a) nitrogen

(b) helium

(c) oxygen

(d) hydrogen

The critical temperature of water is higher than that of O₂ because H₂O molecule has:

(a) fewer electrons than oxygen

(b) two covalent bonds

(c) V-shape

(d) dipole moment

Benzene is oxidized by H₂O₂ in presence of FeSO₄ to:

(a) phenol

(b) cyclohexane

(c) benzaldehyde

(d) benzoic acid

The oxidizing property of H₂O₂ is best explained by assuming that two oxygen atoms in its molecule are:

(a) bonded differently

(b) bonded similarly

(c) bonded covalently

(d) bonded by hydrogen bonds

10 volumes of H₂O₂ has a strength of approximately:

(1) 3%

(2) 30%

(3) 10%

(4) 5%

From the following statements regarding H₂O₂, choose the incorrect statement:

(1) It can act only as an oxidising agent

(2) It decomposes on exposure to light

(3) It has to be stored in plastic or wax lined glass bottles in dark

(4) It has to be kept away from dust

H₂O₂ turns an acidified solution of ........ to orange red.

(a) BaO₂

(b) PbO₂

(c) Na₂O₂

(d) TiO₂

Which is not true in case of H₂O₂?

(1) It is more stable in basic solution

(2) It acts as strong oxidising agent in acid and basic solutions

(3) It is decomposed by MnO₂

(4) It behaves as reducing agent towards KMnO₄

Decmposition of H₂O₂ is retarded by:

(a) acetanilide

(b) alcohol

(c) H₃PO₄

(d) all of these

Point out the incorrect statement.

(1) Hardness of water depends upon its soap consuming power

(2) Temporary hardness is due to bicarbonates of calcium and magnesium

(3) Permanent hardness is due to soluble sulphates, chlorides and nitrates of Ca and Mg

(4) Permanent hardness can be removed by boiling water