ta có :
\(\left\{{}\begin{matrix}2p+n=52\\-p+n=1\end{matrix}\right.\)
=>\(\left\{{}\begin{matrix}p=e=17\\n=18\end{matrix}\right.\)
=>CTHH :Cl (Clo)
Ta có
\(\left\{{}\begin{matrix}2p+n=52\\-p+n=1\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}p=e=17\\n=18\end{matrix}\right.\)
=> Đó là Cl