Fe+2HCl->FeCl_2+H_2

M+2HCl->MCl_2+H_2

Theo PT: n_{Fe}+n_M=n_{H_2}={6,16.2}/{0,082(273+27,3)}=0,5(mol)

Mà n_{Fe}:n_M=2:3

->n_{Fe}=0,2(mol);n_M=0,3(mol)

->M_M={18,4-0,2.56}/{0,3}=24

->M:\ Mg

m_{Fe}=0,2.56=11,2(g)

m_{Mg}=0,3.24=7,2(g)

Đặt n_{Fe}=2x(mol)->n_M=3x(mol)

n_{H_2}={P.V}/{R.T}={6,16.2}/{0,082(273+27,3)}\approx 0,5(mol)

Fe+2HCl->FeCl_2+H_2

M+2HCl->MCl_2+H_2

Theo PT: n_{H_2}=2x+3y=0,5

->x=0,1(mol)

->m_{Fe}=0,1.2.56=11,2(g)

->m_M=18,4-11,2=7,2(g)

->M_M={7,2}/{0,1.3}=24(g//mol)

->M là magnesium (Mg).