Question

Ne nucleus, after absorbing energy, decays into two $\alpha$-particles and an unknown nucleus. The unknown nucleus is:

• A. nitrogen
• B. carbon
• C. boron
• D. oxygen

Answer 1

The correct option is B carbon

Here answer is option B

Atomic no . of Neon $Ne$ is 10

By emission of two $\alpha$-α−particles, atomic no . will be reduced by 4. Atomic no.of unknown element will be

Z= 10−4 = 6Z=10−4=6

Similarly, mass no .of unknown element will be

A=22−2×4 =14A=22−2×4=14

The unknown nucleus is carbon (A=14, Z=6)