EVERYDAY SCIENCE

Detailed explanation-1: -A physical change is generally reversible and there is no formation of a new substance. Sharpening of a pencil is a physical change since shavings that are produced are not new product. It is also an irreversible change because shavings obtained cannot be converted back to the original pencil itself.

Detailed explanation-2: -A physical change occurs when the appearance of a substance changes. In other words, physical changes are changes in size, shape, or state. Sharpening a pencil is a physical change because the pencil because the pencil is still made up of the same materials.

Detailed explanation-3: -Step 1: Identify what type of change is being asked. Step 2: If it is temporary and no new product is formed, then it is a physical change. On the other hand, if it is permanent and one or more new products are formed, then it is a chemical change.

Detailed explanation-4: -Sharpening a pencil does not produce any new substance and shavings that are produced after sharpening the pencil have the same chemical composition (physical change) but the shavings cannot be converted back to pencil (irreversible change).

Detailed explanation-5: -Some common examples of physical changes are: melting, freezing, condensing, breaking, crushing, cutting, and bending.