\(n_A=\dfrac{13}{M_A}\left(mol\right)\)
PTHH: A + Cl2 --to--> ACl2
_____\(\dfrac{13}{M_A}\) ---------->\(\dfrac{13}{M_A}\)
=> \(\dfrac{13}{M_A}\left(M_A+71\right)=27,2=>M_A=65\left(g/mol\right)\)
=> A là Zn
CTPT muối là ZnCl2
\(2A+3Cl_2\xrightarrow{t^o}2ACl_2\\ \Rightarrow n_A=n_{ACl_2}\\ \Rightarrow \dfrac{13}{M_A}=\dfrac{27,2}{M_A+71}\\ \Rightarrow M_A=65(g/mol)(Zn)\\ \Rightarrow CTPT_{muối}:ZnCl_2\)