Atoms and Molecules — Science STD 9 — Question

State whether the following statement is true or false:
Unbalanced forces acting on a body change its shape.

Name the three subatomic particles present in an atom.

Name the excretory organ of:

1. Crab.
2. Insect.

Name the scientist who gave:
Law of constant proportions.

Explain why a legume crop does not require nitrogenous fertilizers?

Under what conditions heat can be given to a substance without raising its temperature?

Give one example of mixed cropping.

State whether the following statements are true or false:
Salt and water can be recovered from an aqueous salt solution by the process of evaporation.