Chemistry : Equilibrium

pH of an aqueous solution of NH₄Cl is

• 7

• >7

• <7

• 1

Which of the following statement is correct ?

• BCl₃ and AlCl₃ are both Lewis acids and AlCl₃ is stronger than BCl₃

• BCl₃ and AlCl₃ are both equally strong Lewis acid

• Both BCl₃ and AlCl₃ are not Lewis acid

• BCl₃ and AlCl₃ are both Lewis acids and BCl₃ is stronger than AlCl₃

Identify the Bronsted acid in the following equation

${\mathrm{PO}}_4^{3-} + {\mathrm{H}}_2\mathrm{O}\hspace{0.17em}\left(\mathrm{l}\right) \to {\mathrm{HPO}}_4^{2-} \left(\mathrm{aq}\right) + {\mathrm{OH}}^{-} \left(\mathrm{aq}\right)$

• PO${}_4^{3-}$

• HPO₄

• H₂O

• OH^-

For the reaction, 2HI (g) $\rightleftharpoons$H₂ (g) + I₂ (g) the degree of dissociation (α) of HI (g) is related to equilibrium constant K_p by the expression

• $\sqrt{\frac{1 + 2{\mathrm{K}}_{\mathrm{p}}}{2}}$

• $\sqrt{\frac{2{\mathrm{K}}_{\mathrm{p}}}{1+ 2{\mathrm{K}}_{\mathrm{p}}}}$

• $\frac{2\sqrt{{\mathrm{K}}_{\mathrm{p}}}}{1 + 2\sqrt{{\mathrm{K}}_{\mathrm{p}}}}$

• $\frac{1 + 2\sqrt{{\mathrm{K}}_{\mathrm{p}}}}{2}$

Rank the following in decreasing order of basic strength

(i) CH₃-CH₂-C≡C^-

(ii) CH₃-CH₂-S^-

(iii) CH₃-CH₂-CO${}_2^{-}$

(iv) CH₃-CH₂-O^-

• (iv) > (i) > (ii) > (iii)

• (i) > (iv) > (ii) > (iii)

• (i) > (iv) > (iii) > (ii)

• (ii) > (i) > (iv) > (iii)

If solubility product of Zr₃(PO₄)₄ is denoted by K_sp and its molar solubility is denoted by S, then which of the following relation between S and K_sp is correct ?

• S = ${\left(\frac{{\mathrm{K}}_{\mathrm{sp}}}{6912}\right)}^{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$7$}\right.}$

• S = ${\left(\frac{{\mathrm{K}}_{\mathrm{SP}}}{929}\right)}^{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$9$}\right.}$

• S = ${\left(\frac{{\mathrm{K}}_{\mathrm{sp}}}{144}\right)}^{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$6$}\right.}$

• S = ${\left(\frac{{\mathrm{K}}_{\mathrm{sp}}}{216}\right)}^{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$7$}\right.}$

In the following compounds, the decreasing order of basic strength will be:

• (C₂H₅)₂NH > NH₃ > C₂H₅NH₂

• (C₂H₅)₂NH > C₂H₅NH₂ > NH₃

• C₂H₅NH₂ > NH₃ > (C₂H₅)₂NH

• NH₃ > C₂H₅NH₂ > (C₂H₅)₂NH

For the following reactions, equilibrium constans are given:

S(s) + O₂(g) $\rightleftharpoons$SO₂(g); K₁ = 10⁵²

2S(s) + 3O₂(g) $\rightleftharpoons \; 2$SO₃(g); K₂ = 10¹²⁹

The equilibrium constant for the reaction,

2SO₂(s) + O₂(g) $\rightleftharpoons \; 2$SO₃(g)

• 10¹⁸¹

• 10⁷⁷

• 10¹⁵⁴

• 10²⁵

In an acid-base titration, 0.1 M HCl solution was added to the NaOH solution of unknown strength. Which of the following correctly shows the change of pH of the titration mixture in this experiment ?

• (D)

• (A)

• (C)

• (B)

Consider the following statements

a) The pH of a mixture containing 400mL of 0.1M H2SO4 and 400 mLof 0.1M NaOH will be approximately 1.3.

b) Ionic product of water is temperature dependent.

c) A monobasic acid with Ka=10^-5 has a pH=5. The degree of dissociation of this acid is 50%.

d) The Le Chatelier’s Principle is not applicable to common-ion effect.

The correct statements are

• b and c

• a,b and d

• a,b, and c

• a and b