Question

D. FIND THE ODD ONE OUT GIVING REASON :
1. Hydrogen, hydrogen sulphide, nitrogen, oxygen, chlorine.
2. Helium, neon, argon, oxygen, krypton.
3. Sodium, potassium, calcium, magnesium, carbon.​

Answer 1

1) Hydrogen Sulphide. (Rest are not compounds)

2) Oxygen. (Rest are inert gases)

3) Carbon. (Rest are s-block elements)

Answer 2

1. odd one out is hydrogen sulphide as the other are one moleculed
2. oxygen as other are noble gases
3. carbon as other are S elements