Question

Which are the correct statements about the Basic Slag:
A. It is a by product from steel industry
B. It contains 8-12% P₂O₅
C. It is an ideal source of Phosphorus for crops in acidic soils
D. It contains about 25% citrate soluble P₂O₅
E. It contain nitrogen as well as potassium

• A. A, B only
• B. A, B, C only
• C. C, D, E only
• D. A, C only

Hint:

Basic Slag = Steel Industry Byproduct. Because it is alkaline, always use it in Acidic Soils. It is a "Citrate Soluble" P-fertilizer, meaning it releases nutrients slowly.

Answer 1

The Correct Option is B

Concept: Basic slag is a byproduct of the steel-making process (specifically the Bessemer and open-hearth processes). It is used as a phosphatic fertilizer and a soil conditioner, particularly valued for its neutralizing properties in specific soil types.

Step 1: Evaluate Statement A and B regarding origin and content.
Statement A is correct: Basic slag is indeed a byproduct generated during the smelting of iron ore to produce steel. Statement B is also correct: The phosphorus content typically ranges between 8% and 12% $P_{2}O_{5}$, depending on the quality of the iron ore used.

Step 2: Evaluate Statement C and D regarding solubility and soil use.
Statement C is correct: Basic slag contains a high amount of calcium and magnesium silicates, giving it a high neutralizing value. This makes it an ideal source of phosphorus for crops grown in acidic soils, as it helps raise the pH while providing nutrients. Statement D is incorrect: While it is citrate-soluble, the concentration of $P_{2}O_{5}$ is not 25%; as noted in Statement B, the total content is much lower.

Step 3: Evaluate Statement E.
Statement E is incorrect: Basic slag is primarily a phosphatic fertilizer. It does not contain significant amounts of Nitrogen or Potassium.