Which of the following reactions does not liberate gaseous product ?

• AlCl₃ + NaOH →

• NaOH + P(white) + H₂O →

• Al + NaOH $\stackrel{∆}{\to }$

• Zn + NaOH $\stackrel{∆}{\to }$

CH₃CH₂OH $\underset{\mathrm{Step}- 1}{\overset{{\mathrm{Cl}}_2}{\to }}$ CH₃CHO $\underset{\mathrm{Step}-2}{\overset{3{\mathrm{Cl}}_2}{\to }}$ Cl₃CCHO

In the above reaction, the role of Cl₂ in Step-1 and Step-2 respectively is:

• oxidation, chlorination

• reduction, chlorination

• oxidation, addition

• reduction,substitution

The number of sigma (σ) and pi ($\mathrm{\pi }$) bonds present in benzene respectively are :

• 12, 6

• 6, 6

• 6, 12

• 12, 3

The standard reduction potentials of Zn²⁺| Zn, Cu²⁺| Cu and Ag⁺| Ag are respectively -0.76, 0.34 and 0.8 V. The following cells were constructed :

(1) Zn | Zn²⁺ || Cu²⁺ | Cu

(2) Zn | Zn²⁺ || Ag⁺ | Ag

(3) Cu | Cu²⁺ || Ag⁺ |Ag

What is the correct order of E${}_{\mathrm{cell}}^{°}$ of these cells?

• 2 > 3 > 1

• 2 > 1 > 3

• 1 > 2 > 3

• 3 > 1 > 2

What is the time (in sec) required for depositing all the silver present in 125 mL of 1 M AgNO₃ solution by passing a current of 241.25 A? (1F = 96500 coulombs)

• 10

• 50

• 1000

• 100

The disperse phase, dispersion medium and nature of colloidal solution (lyophilic or lyophobic) of 'gold sol' respectively are :

• solid, solid, lyophobic

• liquid, liquid, lyophobic

• solid, liquid, lyophobic

• solid, liquid, lyophilic

27.

Electrolysis of X gives Y at anode. Vacuum distillation of Y gives H₂O. The number of peroxy (O-O) bonds present in X and Y respectively are :

• 1, 1

• 1, 2

• zero, 1

• zero, zero

AB is an ionic solid. The ionic radii of A⁺ and B^- are respectively r_c and r_a. Lattice energy of AB is proportional to :

• $\frac{{\mathrm{r}}_{\mathrm{c}}}{{\mathrm{r}}_{\mathrm{a}}}$

• (r_c + r_a)

• $\frac{{\mathrm{r}}_{\mathrm{a}}}{{\mathrm{r}}_{\mathrm{c}}}$

• $\frac{1}{\left({\mathrm{r}}_{\mathrm{c}} + {\mathrm{r}}_{\mathrm{a}}\right)}$

The rate constant of a first order reaction at 27°C is 10^-3 min^-1. The temperature coefficient of this reaction is 2. What is the rate constant (in min^-1 ) at 17°C for this reaction ?

• 10^-3

• 5 × 10^-4

• 2 × 10^-3

• 10^-2

What is the correct order of occurrence (% by weight) in air of Ne, Ar and Kr ?

• Ne > Ar > Kr

• Ar > Ne > Kr

• Ar > Kr > Ne

• Ne > Kr > Ar