\(n_X=\dfrac{3,6}{M_X}\left(mol\right)\)
PTHH: X + S --to--> XS
\(\dfrac{3,6}{M_X}\)-------->\(\dfrac{3,6}{M_X}\)
=> \(\dfrac{3,6}{M_X}\left(M_X+32\right)=8,4\)
=> MX = 24 (g/mol)
=> X là Mg
X + S \(\underrightarrow{t^o}\) XS.
Ta có: \(\dfrac{3,6}{M_X}=\dfrac{8,4}{M_X+32}\) \(\Rightarrow\) MX=24 (g/mol). Vậy kim loại X là magie (Mg).