Question

Which element do not have valency equals to its group number?

• A. Sodium
• B. Magnesium
• C. Oxygen
• D. Potassium

Answer 1

Answer: (C)

Oxygen

Group number of sodium is $1$. Its valency is $1$.

Group number of magnesium is $2$. Its valency is $2$.

Group number of oxygen is $16$. Its valency is $2$.

Group number of potassium is $1$. Its valency is $1$.