A few grams of dried soil were first heated until red hot and then further heated until no more smoke was released. This experiment was to determine
A. amount of water in soil B. percentage of water in soil C. presence of humus in soil D. resistance of laterities to heat E. release of smoke from the soil
Correct Answer: C
Explanation
The correct answer is C: presence of humus in soil.
Explanation: Heating the soil until no more smoke is released is a method to determine the presence of humus. Humus, which is the decomposed organic matter in soil, can release smoke when it is burned due to the volatile organic compounds it contains. Once all the humus is burned off and no more smoke is produced, it indicates that the organic matter (humus) has been fully removed. This experiment helps identify the amount of organic material in the soil.
