Q.1. Match the following and identify the correct option. (2020)
⇒ CO(g) + H2(g) = Water gas or synthesis gas
⇒ Temporary hardness of water is due to bicarbonates of Ca2+ & Mg2+
⇒ B2H6 is a electron deficient compound due to presence of banana bond.
⇒ H2O2 open book like structure which is non-planar
Q.2. The method used to remove temporary hardness of water is : (2019)
(a) Calgon's method
(b) Clark's method
(c) Ion-exchange method
(d) Synthetic resins method
Clark's method is used to remove temporary hardness of water, in which bicarbonates of calcium and magnesium are reacted with slaked lime Ca(OH)2.
Q.3. Which of the following statements about hydrogen is incorrect ? (2016)
(a) Dihydrogen does not act as a reducing agent.
(b) Hydrogen has three isotopes of which tritium is the most common.
(c) Hydrogen never acts as cation in ionic salts.
(d) Hydronium ion, H3O+ exists freely in solution.
Dihydrogen act as reducing agent for eg: 3H2 + N2 → 2NH3
Hydrogen has three isotopes of which protium (1H1) is the most common.
Q.4. (A) H2O2 +O3 → H2O+ 2O2
(B) H2O2 + Ag2O → 2Ag + H2O + O2
Role of hydrogen peroxide in the above reactions is respectively : (2014)
(a) reducing in (A) and (B)
(b) oxidizing in (A) and (B)
(c) oxidizing in (A) and reducing in (B)
(d) reducing in (A) and oxidizing in (B)
H2O2 acts as reducing agent in both the reactions
H2O2 +O3 → H2O+ 2O2
H2O2 + Ag2O → 2Ag + H2O + O2