Question

(A) ${}_{56}^{133}Be+e^{-}{\to }_{55}^{133}Cs+X-ray$
It is a process of K-electron capture.. .
(R) The atomic number decreases by one unit as a result of K-capture.

• A. Both (R) and (A) are true and reason is the. correct explanation of assertion
• B. Both (R) and (A) are true but reason is not correct explanation of assertion
• C. Assertion (A) is true but reason (R) is false
• D. Assertion (A) and reason (R) both are false.
• E. Assertion (A) is false but reason (R) is true

Answer 1

Answer: (A)

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

${}_{56}^{133}Be+e^{-}{\to }_{55}^{133}Cs+X-ray$

It is a process of K-electron capture.In the above equation the product ${}_{55}^{133}Cs$ has 1 electron less than reactant ${}_{56}^{133}Be$,So the atomic number decreases by one unit as a result of K-capture.

So both (R) and (A) are true and reason is the. correct explanation of assertion.

Hence option A is correct.