Question

By placing a soil sample at 105° C for 24 hours in an oven, which of the following statements are correct? (A) Hygroscopic moisture is lost
(B) Capillary water is lost
(C) Free water is lost
(D) Structural water is lost
Which of the above statements are correct?

• A. (A), (B) and (D) only
• B. (B), (C) and (D) only
• C. (A), (B), (C) and (D)
• D. (A), (B) and (C) only

Hint:

Heating soil at 105° C for 24 hours removes hygroscopic moisture, capillary water, free water, and structural water.

Answer 1

The Correct Option is C

Step 1: Impact of Heating Soil to 105° (C)
- (A) Hygroscopic moisture removal: Soil heating at 105° C eliminates hygroscopic moisture, which adheres to soil particles.
- (B) Capillary water loss: Heating also removes capillary water, found within the soil's small pores.
- (C) Free water evaporation: Free water, unbound to soil particles, is lost during heating.
- (D) Structural water release: Heating the soil also causes the release of structural water, which is part of the mineral structure.

Step 2: Summary.
Therefore, all statements (A), (B), (C), and (D) are accurate, making option (3) the correct choice.

Final Answer:
\[ \boxed{3. \, (A), (B), (C) \, \text{and} \, (D)} \]