Lyophobic collloids are:

(1)reversible colloids

(2)irreversible colloids

(3)protective colloids

(4)gum, proteins

The decomposition of H₂O₂ may be checked by adding a small quantity of phosphoric acid. This is an example of:

(a) neutralization           (b) negative catalysis

(c) positive catalysis       (d) catalytic poisoning

Which of the following is not applicable to chemisorption?

1. Its heat of adsorption is high

2. It takes place at high temperature

3. It is reversible

4. It forms unimolecular layer

As₂S₃ sol is

1. possible colloid                 2. negative colloid

3. neutral colloid                  4. none of the above

At the critical micelle concentration (CMC) the surfactant molecule

1. Decompose

2. Dissociate

3. Associate

4. Become completely soluble

Which one has the highest coagulation power?

(1) K⁺

(2) Ca⁺⁺

(3) Al⁺⁺⁺

(4) Sn⁴⁺

The charge on As₂S₃ sol is due to to the adsorbed:-

(1) H⁺

(2) OH^-

(3) O^-2

(4) S^-2

The most suitable electrolyte for the coagulation of arsenic sulphide will be:-

(1) AlCl₃

(2) BaCl₂

(3) NaCl

(4) KCl

According to freundlich adsorption isotherm, which of the following is correct:-

(1) $\frac{\mathrm{x}}{\mathrm{m}}\mathrm{\alpha } \mathrm{p}°$

(2) $\frac{\mathrm{x}}{\mathrm{m}}\mathrm{\alpha } \mathrm{p}$

(3) $\frac{\mathrm{x}}{\mathrm{m}}\mathrm{\alpha } {\mathrm{p}}^{1/\mathrm{n}}$

(4) All are correct for different ranges of pressure

Which one of the following statements is not correct?
(a) Catalyst does not initiate any reaction

(b) The value of equilibrium constant is changed in the presence of a catalyst in the reaction equilibrium

(c) Enzymes catalyse mainly biochemical reaction

(d) Coenzymes increase the catalytic activity of enzyme