Electronic configuration of P ‌1s22s23p63s23p3 ⇒‌‌s‌electron ‌=6,p‌electron ‌=9 ‌s:p⇒6:9‌ or ‌2:3‌‌...‌ (i) ‌ Electronic configuration of Ca ‌1s22s22p63s23p64s2 ‌⇒‌‌s‌electron ‌‌‌=8,p‌electron ‌=12 ‌‌‌s:p⇒8:12‌ or ‌2:3‌‌...‌ (ii) ‌ Hence, P and Ca have same ratio of S‌electron ‌‌‌ and p‌electron ‌‌‌.
