Question

Which of the following with respect to the Modern Periodic Table is NOT correct?

• A. It has 18 groups and 7 periods.
• B. The number of shells increases as we go down the group.
• C. The elements present in the same group have same number of valence electrons.
• D. Na, Mg and S belongs to the 4th period of the Modern Periodic Table

Answer 1

Answer:

D. Na, Mg and S belongs to the 4th period of the Modern Periodic Table

Sodium (Na), Magnesium (Mg), and Sulfur (S) are elements that belong to the 3rd period, not the 4th period, of the Modern Periodic Table