Question

Which of the following elements will show similar chemical properties with an element that has an atomic number(Z) of 15?

• A. Be (Z = 4)
• B. Ne (Z = 10)
• C. O (Z = 8)
• D. N (Z = 7)

Answer 1

The correct option is D N (Z = 7)

Down a group, elements have the same number of valence electrons and identical outer shell electronic configuration. So, elements under the same group have similar chemical properties.

So for an element having atomic number 15, the electronic configuration is 2,8,5

Also, for the following elements, the electronic configuration is,
Be(Z - 4): 2, 2
Ne(Z - 10): 2, 8
O(Z - 8): 2, 6
N(Z - 7): 2, 5

Since out of the given elements, only nitrogen has the same number of valence electrons and identical outer shell electronic configuration. Therefore, nitrogen is the element that will have similar properties with the element having an atomic number of 15