Question

Explain about physical and chemical changes with examples :)

Answer 1

Answer:

•Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.

•Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions.

•Examples of physical change include changes in the size or shape of matter. Changes of state—for example, from solid to liquid or from liquid to gas—are also physical changes. Some of the processes that cause physical changes include cutting, bending, dissolving, freezing, boiling, and melting.

•Examples of Chemical Change in Everyday Life:

☞︎︎︎Burning of paper and log of wood.

☞︎︎︎Digestion of food.

☞︎︎︎Boiling an egg.

☞︎︎︎Chemical battery usage.

☞︎︎︎Electroplating a metal.

☞︎︎︎Baking a cake.

☞︎︎︎Milk going sour.

☞︎︎︎Various metabolic reactions that take place in the cells.

Thank you.

Answer 2

Answer

$\bigstar$ Physical changes :-

• The change in which the material goes in change on it's physical properties is called as a physical change. It can also be classified as reversible and irreversible, which means it can be converted back to it's original state and cannot be converted back. There
• This type of change only takes place in liquids. If there is a change in any item's shape, colour, size, state, weight and temperature then we can classify them as physical changes. There is no new substance formed.

Examples :-

1. Freezing of water to form ice.
2. Breaking of an egg.
3. Cutting of wood.
4. Freezing if milk.
5. Cutting of paper.

$\bigstar$ Chemical changes :-

• The change in which a material goes in change by chemically or the change may form new substance when they come under change. The old material will vanish and to complete this cycle the new substance is formed out of it.
• These changes are generally classified as irreversible changes, which means they cannot come back to their original state.

Examples :-

1. Burning of paper.
2. Curding the milk.
3. Digestion of food.
4. Cooking of food.
5. Rusting of iron.
6. Mixing of acid and base.