Question

Which of the following is not a chemical change?
A.Melting of ice
B.Carbon cycle
C.Dehydration of substances
D.Fermentation of substances

Answer 1

Hint- As we see in our environment that changes in which one or more new substances are formed is called a chemical change.

Complete step by step answer:
We can call chemical change a chemical reaction where the physical character of a substance may change. Examples are burning of any substances like wood, paper, rusting of iron.
We know that Melting is a physical process that results in the transformation of substances from a solid to a liquid state. The energy of a substance increases internally, after the application of pressure or heat, resulting in a rise of temperature to the melting point of a substance, at which the ordering of molecular entities or ionic in the solid breaks down into a less ordered state and the solid changes into a liquid phase.
Hence we can conclude that the answer is A. Melting of ice
Additional information: The difference between a chemical reaction and a physical reaction is composition. In a chemical reaction, there is always a change in the composition of the substances; in a physical change there is a difference in the smell, properties, appearance, of a sample of matter without a change in its composition.

Note: When two or more than two compounds are mixed and an odour is present, a chemical reaction has already taken place. For example, when an egg starts smelling after a duration, (a rotten egg) a chemical reaction has taken place. This is a result of a chemical decomposition.