The gas we use in the kitchen is called liquified petroleum gas (LPG). In the cylinder it exists as a liquid. When it comes out from the cylinder it becomes a gas (Change - A) then it burns (Change - B). The following statements pertain to these changes. Choose the correct one.

(i) Process - A is a chemical change.


(ii) Process -B is a chemical change.


(iii)Both processes A and B are chemical changes .


(iv) None of these processes is a chemical change.


Process A is a physical change because no new substance is formed. The LPG in cylinder is in liquid form because of high pressure. When it comes out from the cylinder, it turns into a gaseous form. Thus, it is a physical change.


Process B is a chemical change because burning of gas is a chemical change.


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