Government College Peshawar

KPPSC SS Chemistry test 2023

1. Fog is an example of which type of colloidal system?

(a) Gas in liquid

(b) Solid in gasLiquid in gas

(c) Gas in gas

(d) Liquid in gas

Answer: (b)

2. Which of the following properties of colloids does not depend on the charge on particles?

(a) Coagulation

(b) Electro-osmosis

(c) Electrophoresis

(d) Tyndall effect

Answer: (d)

3. The term used to determine the protecting power of a lyophilic colloid is

(a) oxidation number

(b) coagulation value

(c) gold number

(d) critical micelle concentration

Answer: (c)

4. This method is commonly used for destruction of colloid

(a) Addition of electrolytes

(b) Condensation

(c) Dialysis

(d) Filtration by animal membrane

Answer: (a)

5. Which of the following compounds form micelles, if their concentration is increased in aqueous solution?

(a) Urea

(b) Glucose

(c) Pyridinium chloride

(d) Dodecyl trimethyl ammonium chloride

Answer: (d)

6. If the concentration of surfactant molecules increases above the critical micelle concentration (CMC), then they

(a) become soluble

(b) dissociate

(c) associate

(d) decompose

Answer: (c)

7. The ability of an ion to coagulate a given colloid is dependent on the

(a) only charge

(b) magnitude

(c) both magnitude and charge

(d) sign of the charge

Answer: (c)

8. The diameter of particles in colloidal system is

(a) 10-9 m to 10-6 m

(b) 10-10 m to 10-4 m

(c) 10-12 m to 10-9 m

(d) 10-7 m to 10-5 m

Answer: (a)

9. Which of the following is an associated colloid?

(a) Soap

(b) Sol of gold

(c) Proteins

(d) Starch

Answer: (a)

10. The position occupied by non-polar hydrophobic and polar hydrophilic group in a micelle is

(a) non-polar towards the outside and polar towards inside

(b) polar towards the outside and non-polar towards inside

(c) both present only at the surface

(d) both distributed throughout

Answer: (b)

Rectified spirit contains

(A) 18% ethanol

(B) 75% ethanol

(C) 95.6% ethanol

(D) 100% ethanol

BS chemistry merit list Government college peshawar