Question

Name an define with example
a) slow and fast change
b) physical and chemical changes
c) desirable and undesirable changes​

Answer 1

Answer:

The changes that take a long duration of time to complete, are called slow changes. This duration can be in hours, days or even months. The changes that are completed in short or very short duration of time are called fast changes.

Remember that a physical change is a change in properties such as texture, shape, or state, while a chemical change represents the formation of a new substance after atoms are rearranged in a chemical reaction.

Desirable Changes: Those changes which are desired to occur that is, we want them to take place are known as desirable changes. Examples: ripening of fruits, germination of seeds etc. Undesirable change: Those changes which we do not want to take place are called undesirable changes.