Elements \(P\) has an atomic number of 12 while element \(Q\) has an atomic number 15. Combination of \(P\) and \(Q\) gave a compound \(P _{m} Q _{n}\). the respective values of \(m\) and \(n\) are ____________
A. 2 and 2 B. 2 and 3 C. 3 and 2 D. 2 and 1
Correct Answer: C
Explanation
\begin{aligned} &{ }_{12} P -1 s ^{2} 2 s ^{2} 2 p ^{6} 3 s ^{2}, P \text { in ionic form } P ^{2+} \\ &{ }_{15} Q -1 s ^{2} 2 s ^{2} 2 p ^{6} 3 s ^{2} 3 p ^{3} Q \text { in ionic form } Q ^{3} \end{aligned}
