Which of the following is the lightest isotope used as a primary ion?
A. He
B. 2He
C. 3He
D. 3H
Answer:C
Which of the following is the lightest isotope used as a primary ion?
A. He B. 2He C. 3He D. 3H
Explanation: 3He is the lightest isotope used as a primary ion. Though hydrogen is lightest it is not used.