In the following questions a statement of Assertion (A) followed by a statement of Reason (R) is given. Choose the correct option out of the choices given below each question.

Assertion (A): At constant temperature, pVvs V plot for real gases is not a straight line.


Reason (R): At high pressure all gases have Z > 1 but at intermediate pressure most gases have Z < 1.


(i) Both A and R are true and R is the correct explanation of A.


(ii) Both A and R are true but R is not the correct explanation of A.


(iii) A is true but R is false.


(iv) A is false but R is true.



(ii)

We know that at constant temperature, pV vs V plot for real gases is not a straight line.


This is because, for pV vs V graph to be straight line, the volume of the gas should be negligible, but it is not possible for the real gases, because they have some volume and hence they show deviation from the straight line.


Now discussing reason,


At high pressure all gases have Z > 1 but at intermediate pressure most gases have Z < 1, this statement is true but it is not the correct explanation of Assertion.


Hence, (ii) is correct option.


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