Atomic Structure Question 91
Question: The number of electrons and neutrons of an element is 18 and 20 respectively. Its mass number is [CPMT 1997; Pb. PMT 1999; MP PMT 1999]
Options:
A) 17
B) 37
C) 2
D) 38
Show Answer
Answer:
Correct Answer: D
Solution:
No. of proton and no. of electron = 18 $ [Ar_18^{36}] $ and No. of neutron = 20 Mass number = P + N = $ 18+20=38. $