Em tham khảo nha:
\(\begin{array}{l}
a)\\
CTHH:{X_2}{O_5}\\
{M_{{X_2}{O_5}}} = 2{M_{C{l_2}}} = 2 \times 71 = 142g/mol\\
\Rightarrow 2{M_X} + 16 \times 5 = 142 \Rightarrow {M_X} = 31g/mol\\
\Rightarrow X:Photpho(P)\\
b)\\
{M_A} = 142g/mol\\
CTHH:{P_2}{O_5}\\
c)\\
{m_A} = 142 \times 1,6605 \times {10^{ - 24}} = 2,35791 \times {10^{ - 22}}(g)
\end{array}\)
