Assertion : Sodium reacts with oxygen to form `Na_2O_2` but potassium reacts with oxygen to form `KO_2`.
Reason : Potassium is more reactive than sodium.

Options

A. If both (A) and (R) are correct and (R) is the correct explanation of (A).
B. If both (A) and (R) are correct, but (R) is not the correct explanation of (A).
C. If (A) is correct, but (R) is incorrect.
D. If both (A) and (R) are incorrect.

Answer

B

Explanation

Due to bigger size of `K^(+)` than `Na^(+)`, it has a weak positive field around it which cannot prevent peroxide ion (`O_2^(2-)`) to combine with another oxygen atom to form superoxide, `O_2^(-)`.