Question

When a small amount of garden soil is put into a glass jar containing water, stirred and allowed to the stand for two hours, The layer from top to bottom would be-

• A. Debris, water, sand and clay
• B. Humus, water clay and sand
• C. Debris, clay, gravel, and sand
• D. Humus, clay gravel and sand

Answer 1

The correct option is B

Humus, water clay and sand

The correct option is B:

Explanation of correct option:

Humus:

1. The particles which remain floating on water are humus, the dead and decaying organic matter.
2. It is rich in nutrients and hence enhances plant growth.

Water:

1. The water forms a film around the soil particles, dissolving minerals and nutrients to form a soil solution.
2. It displaces air spaces present in the soil.

.Clay:

1. Some particle that remains dispersed in water above the silt layer is called clay particles.
2. The size of the clay particles ranges less than $0.005mm$and hence are the smallest soil particles

Sand:

1. The sand particles are big and heavy.
2. They settle at the bottom.
3. The size of the sand particles ranges from $0.05mm$ to $2.00mm$and hence, these particles can be seen easily with naked eyes.
4. These particles are coarse to touch.

Explanation of incorrect option:

Option A:

The sand is present at the bottom in stirred soil so this option is incorrect.

Option C:

1. The size of the gravel particles is greater than $2mm$ in diameter and hence, these particles can be picked up by hand.
2. The gravel is present below of sand. so this option is incorrect.

Option D:

The gravel present below of sand layer. So, this option is incorrect.

Final answer: When a small amount of garden soil is put into a glass jar containing water, stirred and allowed to the stand for two hours, The layer from top to bottom would be- humus, water clay and sand.