Question

If an element is in group 15 of a modern periodic table then the number of valence electrons it has is

• A. 1
• B. 15
• C. 5
• D. 7

Answer 1

The correct option is C

5

All the elements of the same group in a periodic table have same number of valence electrons. Whereas all the elements of the same period have the same number of shells.
The group number helps us in knowing the number of valence electrons of an atom of an element. Since the group number of the given element is 15, which is more than 10, we can find the number of valence electrons by subtracting 10 from the given group number. This means the number of valence electrons is 5.