Among the following, the species having square planar geometry for central atom are
(i) XeF_4, (ii) SF_4, (iii) [NiCl₄]^2- ,(iv) [PdCl₄ ]^2-

• (i) and (iv)

• (i) and (ii)

• (ii) and (iii)

• (iii) and (iv).

The de Broglie wavelength associated with a ball of mass 1kg having kinetic energy 0.5 J is

• 6.626 $\times$ 10^-34 m.

• 13.20 $\times$ 10^-34 m.

• 10.38 $\times$ 10^-21m.

• 6.626 $\times$10^-34$\stackrel{°}{\mathrm{A}}$.

Dominance of strong repulsive forces among the molecules of the gas (Z = compressibility factor)

• depends on Z and indicated by Z = 1

• depends on Z and indicated by Z > 1

• depends on Z and indicated by Z < 1

• is independent of Z.

40 mL of 0.1 M ammonia solution is mixed with 20 mL. of 0.1 M HCl. What is the pH of the mixture? (pK_b, of ammonia solution is 4.74)

• 4.74

• 2.26

• 9.26

• 5.00

For a spontaneous process the correct statement is

• entropy of the system always increases.

• free energy of the system always increases.

• total entropy change is always negative.

• total entropy change is always positive.

For a phase change

${\mathrm{H}}_2{\mathrm{O}}_{\left(\mathrm{l}\right)} \underset{0^{°}\mathrm{C}, 1 \mathrm{bar}}{\rightleftharpoons } {\mathrm{H}}_2{\mathrm{O}}_{\left(\mathrm{s}\right)}$

• $∆\mathrm{G} = 0$

• $∆\mathrm{H} = 0$

• $∆\mathrm{S} =0$

• $∆\mathrm{U} = 0$

The enthaply change ($∆\mathrm{H}$) for the reaction

       $$\begin{gathered} {\mathrm{N}}_{2\left(\mathrm{g}\right) }+ 3{\mathrm{H}}_{2\left(\mathrm{g}\right)} \to 2{\mathrm{NH}}_{3\left(\mathrm{g}\right) \\ } \end{gathered}$$

is -92.38 kJ at 298K . The internal energy change $∆\mathrm{U}$ at 298K is

• -92.38 kJ

• -87.42 kJ

• -97.34 kJ

• -89.9 kJ

Assertion : Molecular nitrogen is less reactive than molecular oxygen.

Reason : The bond length of N₂ is shorter than that of oxygen.

• If both assertion and reason are true and reason is the correct explanation of the assertion.

• If both assertion and reason are true but reason is not the correct explanation of the assertion.

• If assertion is true, but reason is false.

• Both assertion and reason are false statements.

Assertion : Water in liquid state is more stable than ice at room temperature.

Reason : Water in liquid form has higher entropy than ice.

• If both assertion and reason are true and reason is the correct explanation of the assertion.

• If both assertion and reason are true but reason is not the correct explanation of the assertion.

• If assertion is true, but reason is false.

• Both assertion and reason are false statements.

Borax is used as a cleansing agent because on dissolving in water it gives

• alkaline solution

• acidic solution

• bleaching solution

• basic solution.