Question

Choose the odd one from the following :
a. He
b. Ne
c. Cl
d. Ar

Answer 1

c) Cl ✅

Step-by-step explanation:

The odd one out is "c. Cl" (chlorine) because the other elements are noble gases from the periodic table (a. He - helium, b. Ne - neon, d. Ar - argon), which have a full valence electron shell and are chemically inert. Chlorine, on the other hand, is a halogen and is highly reactive due to its need to gain one more electron to complete its valence electron shell.