Question

Statements (A, B, C, D) in list I have to be matched with statements (1,2,3,4) list II.

Answer 1

1. Oxalic acid, $H_2{C}_{2}O4$, a weak polyprotic acid. A diprotic acid ionises stepwise. The first anion is a weaker base than the second, for the first ionisation is more complete than the second.

$H_2{C}_2{O}_4\rightleftharpoons H^{+}+C_2{O}_4^{2-}$,

Thus it is a weak electrolyte.

2. The nickel-cadmium battery ($Ni-Cd$ battery or $Ni-Cd$ battery) is a type of rechargeable battery using nickel oxide hydroxide and metallic cadmium as electrodes.

3. A hydrogen-oxygen fuel cell is a nonpolluting clean fuel since the only combustion product is water.

4. Cathode: $Pb{O}_2\left(s\right)+2e^{-}+4H^{+}\left(aq\right)+S{O}_4^{2-}\left(aq\right)\to PbS{O}_4\left(s\right)+2H_{2}O\left(l\right)$ . When a lead storage battery discharges, lead(II) sulphate forms on both electrodes.

Thus, a correct answer is A-3, B-1, C-4, D-2.