Engineering Questions with Answers - Multiple Choice Questions

# Geotechnical Engineering MCQs – Soils Classification – Specific Surface

1 - Question

1. Specific surface is termed as __________ a) Total volume of soil particles b) Total area of soil particles c) Total surface area in a unit mass d) Ratio of total surface to the total volume
View Answer Answer: c Explanation: Specific surface is usually defined as the total surface area of the soil particle in a unit mass.

2 - Question

2. Specific surface of the soil particle increase very rapidly, as the grain size ____________ a) Increases b) Decreases c) Bulges d) None of the mentioned
View Answer Answer: b Explanation: The subdivision of a mass yields greater surface area than the same mass itself. The specific surface of a mass increases as the grain size decreases.

3 - Question

3. A factor, which is important for the magnitude of specific surface of soil particles is__________ a) Grain shape b) Grain size c) Both size and shape d) Grain molecular structure
View Answer Answer: a Explanation: Specific surface varies for different shapes of particle having the same mass. Hence grain shape is important factor for determining specific surface.

4 - Question

4. The specific surface of a soil particle will be ___________ a) Proportional to inter-molecular surface b) Inversely proportional to electric force c) Proportional to the compressive force d) Directly proportional to electric force

5 - Question

5. The harmonic diameter, can be found out by using __________ a) kozney’s method b) casagrande method c) Skempton’s method d) Atterberg method

6 - Question

6. Specific surface of a soil is related with __________ a) Chemical properties of the soil b) Physical properties of the soil c) General characteristic of the soil d) All of the mentioned
View Answer Answer: b Explanation: As specific surface is associated with surface characteristics of a particle, therefore it is related with physical properties.

7 - Question

7. Microscopic soil particles have a very ___________ a) Larger specific surface b) A larger volume c) Small specific surface d) Larger diameter
View Answer Answer: a Explanation: As the specific surface increases as the size of the grain decreases. Therefore Microscopic particles have a large specific surface.

8 - Question

8. Specific surface(SS) can also expressed as ________ a) Surface area of the particle per unit volume b) Physical properties of the soil c) Moisture content of the soil d) None of the mentioned
View Answer Answer: a Explanation: From the expression, specific surface = surface area of particle/volume of the particle, it can be seen that specific surface is the surface area of a particle.

9 - Question

9. Permeability of the soil depends on __________ a) Size of the soil particle b) Moisture present in soil c) Specific surface of the soil particle d) Density of the soil
View Answer Answer: c Explanation: Permeability of soil greatly depends on the specific surface of the soil because of the viscous effects associated with surface characteristics of the grains.

10 - Question

10. Chemical activity of a clay mineral depends on __________ a) Electric charge b) Surface area c) Compactness d) Unit mass
View Answer Answer: b Explanation: The chemical activity of the clay mineral depends upon the surface area, because of the electrical charge of clay minerals is high per unit mass.