When 750 mL of 0.5 M HCl is mixed with 250 mL of 2 M NaOH solution, the value of pH will be

• pH = 7

• pH > 7

• pH < 7

• pH = 0

822.

The most stable carbonium ion among the following is

• ${\mathrm{C}}_6{\mathrm{H}}_5 -{\mathrm{CH}}_2\stackrel{+}{\mathrm{C}}{\mathrm{H}}_2$

• ${\mathrm{CH}}_3\stackrel{+}{{\mathrm{CH}}_2}$

• ${\mathrm{C}}_6{\mathrm{H}}_5 -\stackrel{+}{\mathrm{C}}-{\mathrm{C}}_6{\mathrm{H}}_5$

• ${\mathrm{C}}_6{\mathrm{H}}_5\stackrel{+}{\mathrm{C}}{\mathrm{H}}_2$

Aqueous solution of AlCl₃ is acidic towards litmus while of NaCl is not. The correct reason behind this is

• AlCl₃, furnishes OH^- ion in the solution

• AlCl₃, furnishes H⁺ ion in the solution

• AlCl₃, furnishes both H⁺ well as OH^- ion in the solution

• AlCl₃, is the salt of strong base and strong acid

The melting point of solid substances is directly proportional to pressure acting on them. However, ice-melts at a temperature lower than its usual melting point, when the pressure increases. This is because

• ice is not a true solid

• the bonds break under pressure

• ice is less denser than water

• pressure generates heat

100 mL of a solution contains 2 g of acetic acid and 3g of sodium acetate providing K_a =1.8 x 10^-5 , then choose the correct option.

• This solution is basic in nature

• This solution is acidic in nature

• This solution is amphoteric in nature

• This solution is neutral in nature

Both Mg and Fe metal can reduce copper from a solution having Cu²⁺ ion, according to equilibria.

Mg_(s) + Cu²⁺ $\rightleftharpoons$ Mg²⁺ + Cu_(s); K₁ = 6 x 10⁹⁰

Fe_(s) + Cu²⁺ $\rightleftharpoons$ Fe²⁺ + Cu_(s); K₂ = 3 x 10²⁶

Choose the correct option regarding above equilibrium

• Mg removes more Cu²⁺ from solution

• Fe removes more Cu²⁺ from solution

• Both will equally remove Cu²⁺ from solution

• Both metals cannot remove Cu²⁺ from solution

At radioactive equilibrium, the ratio between two atoms of radioactive elements A and B is 3.1 x 10⁹ : 1. If the half-life period of A is 2 x 10¹⁰ yrs, then the half-life of B is

• 9.54 yrs

• 2.14 yrs

• 3.29 yrs

• 6.45 yrs

The dissociation equilibrium of a gas AB₂ can be represented as

2AB₂ (g) $\rightleftharpoons$2AB (g) + B₂(g)

The degree of dissociation is 'x' and is small compared to 1. The expression relating the degree of dissociation (x) with equilibrium constant KP and total pressure p is

• $\frac{2K_p}{p}$

• ${\left(\frac{2K_p}{p}\right)}^{\frac{1}{3}}$

• ${\left(\frac{2K_p}{p}\right)}^{\frac{1}{2}}$

• $\frac{K_p}{p}$

A buffer solution is prepared in which the concentration of NH₃ is 0.30 M and the concentration of N${\mathrm{H}}_4^{+}$ is 0.20 M. If the equilibrium constant, K_b for NH₃ equals 1. 8 x 10^-5, what is the pH of this solution? (log 2. 7 =0. 43).

• 9.43

• 11.72

• 8.73

• 9.08

Which of the following is least likely to behave as Lewis base?

• NH₃

• BF₃

• OH^-

• H₂O