2H₂O $\stackrel{\mathrm{Electrolysis}}{\to }$ 2H₂ + O₂

2mol                              1mol

2 x 18 = 36 gm

Since, 36 gm of H₂O produce 1 mole of oxygen.

$\therefore$ 108 gm of water will produce oxygen = $\frac{108}{36}$= 3 mol

pH of 0.001 M solution of HCl is 3.

[H⁺] = 0.001

pH = -log [H⁺]

     = -log [10^-3]

     = 3

C₂H₅OH reacts with CH₃COOH and gives ethylethanoate. It is an ester and has fruity smell.

C₂H₅OH + CH₃COOH $\stackrel{\mathrm{conc}. {\mathrm{H}}_2{\mathrm{SO}}_4}{\to }$ CH₃COOC₂H₅ + H₂O

                                                        Ester

The ionisation potential decreses in group on moving downward because atomic radius increases hence, the correct order is

Be > Mg > Ca

Bleaching powder is obtained by treating Cl₂ with lime water.

Ca(OH)₂ + Cl₂ $\to$ CaOCl₂ + H₂O

The hybridisation state of carbon in fullerene is sp².

 ${\mathrm{PbCl}}_2\rightleftharpoons \underset{\mathrm{s}}{{\mathrm{Pb}}^{2+}} + \underset{2\mathrm{s}}{2{\mathrm{Cl}}^{-}}$

K_SP = (S) (2S)²

1 x 10^-6 = 4S³

S = ${\left(\frac{1}{4}\times {10}^{-6}\right)}^{1/3}$ = (0.25 x 10^-6)^1/3

Therefore, temperature solubility of PbCl₂ in mol/L is (0.25 x 10^-6)^1/3

Calcium sulphate hemihydrate (CaSO₄.$\frac{1}{2}$H₂O) is called plaster of paris.

When dihydroxy acetone reacts with HIO₄, products formed are HCHO and CO₂.

D₂O is called heavy water. It is used as moderator in nuclear reactor.