Question

Which substance can not be broken down by a chemical change?(1) ammonia (2) methanol (3) propane (4) phosphorous

Answer 1

Answer:  Phosphorous

Explanation:  Chemical Changes are the changes which are responsible for the changes in the intrinsic and chemcial nature of the substance.

When a compound undergoes a chemical change ,it gets converted into other compound or they will get broken down into their constitiuent element.

Thus out of the given options, Phosphorous is the one which cannot be broken down by a chemical change because it is itself an element.

Answer 2

Answer is (4) Phosphorous

bec it is already an element