1. Which of the following clay minerals are considered as colloidal?
a) Kaolinite
b) Dichite
c) Attapulgite
d) All of the mentioned
Explanation: As entire clay particle has a greater dimension than 1μ, all of the clay minerals are considered as colloidal.
2. Clay minerals are classified in to ____________
a) 3
b) 4
c) 7
d) 6
Explanation: Kaolinite, montmorillonite, illite, playgorskite are the types of clay minerals.
3. Chemically, the clay minerals are silicates of ____________
a) Aluminum
b) Iron
c) Magnesium
d) All of the mentioned
Explanation: Since minerals contain alkaline and/or alkaline earth as essential component they contain alkaline mineral such as aluminium, iron, magnesium.
4. Clay is essentially made of extremely __________
a) Large particles
b) Small particles
c) Intermediate particles
d) None of the mentioned
Explanation: Clay is generally made of small particles of either a book of sheets like units (or) bundle of tubes or fibers.
5. There are _________ possible type of attractive forces.
a) 4
b) 5
c) 6
d) 2
Explanation: There are 6 types of attractive forces.
i) vanderwaal’s London force
ii) hydrogen
iii) bond, cationic linkage
iv) di-pole cationic linkage
v) water dipole linkage
vi) ionic bond.
6.Which of the following type of attraction force act between two-particle carrying negative charges?
a) Vander Waal’s London force
b) Water-dipole linkage
c) Ionic bond
d) Cationic linkage
Explanation: The cationic linkage act as bridge between two adjacent particle carrying negative charges.
7. The repulsive force between the soil colloids become effective when?
a) They approach other
b) They combine with each other
c) They are at a distance
d) They overlap
Explanation: When two soil colloids approach each other close enough, the double layer tend to overlap and interact.
8. Which of the following, is considered to be a universal attractive force?
a) Gravitational force
b) Dipole-cationic linkage
c) Ionic bond
d) Vander Waal’s London force
Explanation: Since the vanderwaal’s London force effective in many soils, where other is not it is considered as a universal attractive force.
9. The type of bond in kaolinite crystal is _____________
a) Cationic linkage bond
b) Hydrogen bond
c) Linkage bond
d) Ionic bond
Explanation: The edges of two kaolinite crystal are joined by two cations. Hence cationic linkage bond exist in kaolinite crystal.
10. The repulsive force in soil particle is due to ____________
a) Particles are attracted to each other
b) Particles are similarly charged
c) Particles are oppositely charged
d) None of the mentioned
Explanation: Since the particles are similarly charged (negative) they repel each other causing repulsive force.