In of the following process, chemical change occurs?
1)evaporation
2)burning
3)moisturisation
4)boiling

Evaporation

Burning – is the process in which a chemical change occurs.
 
Chemical Change is a process in which a substance combines with another to form a new substance by chemical reactions.
 
In the above given process, new products are formed after a chemical reaction in which the products are reversible.
 
However, in burning, a new substance is formed which is irreversible.
 
Example: Ash is formed after burning wood, Carbon dioxide and water are formed after burning methane gas in air, etc.

2) burning
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2)Burning will be the ans because if any thing get burn the only thing which is left behind is ash.

2nd option is correct

A chemical change occurs when one substance gets converted into another due to a chemical process. This change is very often not reversible.

Among the given options, the process that causes a chemical change is 2) burning. When a substance is burnt, it cannot be restored to its original form. For example, when a paper is burnt, it is converted to ashes. It is not possible to reconvert the ash into paper.

Burning is a chemical change as new product I created that is water vapour and heat energy

Burning- as it is irreversible

During a chemical change , always a new product is formed with different composition.
ENERGY May be given out or absorbed during chemical change .
So, among the above given options:

Burning involves chemical changes.

Example:
Burning of candle:

Candle burns to give heat , light energy along with water vapour and CO2.
It's irreversible change.

Remaining options are physical change examples

In burning chemical change occurs as it leaves residues as ash.

The pressure law states

"for a fixed mass of gas, at a constant volume, the pressure (p) is directly proportional to the absolute temperature (t)."

pressure  ∝  temperature

pressure/ temperature = constant