Soil Science - Study Mode

[#596] Which extract is used for determination of CEC
Correct Answer

(A) 1N NH 4 OAC

Explanation

Solution: 1N NH 4 OAC (ammonium acetate) is the extract used for the determination of CEC, Cation exchange capacity. In this method, the soil is leached with an excess of neutral, in 1 N ammonium acetate solution to remove the exchangeable cations and to saturate the exchange material with ammonium. Sodium is a saturated cation and is moved by an ammonium cation. The CEC is calculated based on the concentration of sodium ions in the extract.

[#597] COLE is known as
Correct Answer

(D) All of the above

Explanation

Solution: COLE is known as the Coefficient of linear extensibility. It is also known as Potential volume exchange as well as a swell index. The coefficient of linear extensibility is a quantitative expression to classify soils according to their swell and shrink potential and its estimation is crucial for engineering and agronomic applications.

[#598] Range of Void Ratio (e) is
Correct Answer

(C) 0.3 - 2.0

Explanation

Solution: Void ratio is defined as the ratio of the volume of voids to the total volume of soil solid. It is a mixture is the ratio of the volume of voids to the volume of solids. It is denoted by the letter 'e'. The range of Void ratio (e) is 0.3 - 2.0. if the void ratio is high (loose soils) voids in a soil skeleton tend to minimize under-loading-adjacent particles contract. Whereas, when the void ratio is relatively small (dense soils), indicates that the volume of the soil is vulnerable to increase under loading-particles dilate.

[#599] Oxidation state of sulphur
Correct Answer

(A) +6 to -2

Explanation

Solution: The oxidation state of Sulphur is +6 to -2. A monatomic ion’s oxidation state is the same as its charge. The oxidation state shows the total number of electrons that have been removed from an element (a positive oxidation state) or added to an element (a negative oxidation state) to get to its present state.

[#600] Soil conservation is
Correct Answer

(A) Protection against loss

Explanation

Solution: Soil preservation is the prevention of loss of the top layer of the soil from erosion or prevention of reduced fertility caused by over usage. Thus, soil conservation can be called Protection against loss. Soil conservation farming involves no-till farming, green manures and soil enhancing practices which make it hard for soils to be equalized.