Giải nhanh giúp mình bài 13 với ạ

`a)`

`d_{B//O_2}={M_B}/{M_{O_2}}=1,375`

`->M_B=1,375.32=44(g//mol)`

`d_{A//B}={M_A}/{M_B}=0,773`

`->M_A=0,773.44\approx 34(g//mol)`

`b)`

`n_{O_2}={16}/{32}=0,5(mol)`

`V_A=3V_{O_2}`

`->n_A=3n_{O_2}=1,5(mol)`

`->m_A=1,5.34=51(g)`

$\rm a)\\d_B/O_2=1,375\\\xrightarrow[]{}M_B=1,375.32=44(g/mol)\\d_A/B=0,773\\\xrightarrow[]{}M_A=0,773.44≈34(g/mol)\\b)\\n_{O_2}=16:32=0,5(mol)\\Mà:V_A=3V_{O_2}\\\xrightarrow[]{}n_{A}=3n_{O_2}=3.0,5=1,5(mol)\\\xrightarrow[]{}m_A=1,5.34=51(g)$