Gọi kim loại hóa trị I là M
\(pthh:M_2O+H_2SO_4\rightarrow M_2SO_4+H_2O\)
Đặt \(n_{M_2O}=n_{H_2SO_4}=n_{M_2SO_4}=x\left(mol\right)\)
\(\Rightarrow m_{MO}=n\cdot M=x\cdot\left(2M+16\right)=2x\left(M+8\right)\text{ }\left(g\right)\\ \Rightarrow m_{H_2SO_4}=n\cdot M=x\cdot98=98x\left(g\right)\\ \Rightarrow m_{d^2\text{ }H_2SO_4}=\frac{98x\cdot100}{19,6}=500x\left(g\right)\\ \Rightarrow m_{d^2\text{ }sau\text{ }pứ}=2x\left(M+8\right)+500x=2x\left(M+258\right)\left(g\right)\\ \Rightarrow m_{M_2SO_4}=\frac{2x\left(M+258\right)\cdot25,2}{100}=0,504x\left(M+258\right)\left(g\right)\\ \Rightarrow x\left(2M+96\right)=0,504x\left(M+258\right)\\ \Rightarrow M+48=0,252\left(M+258\right)\\ \Rightarrow M+48=0,252M+65,016\\ \Rightarrow M=23\left(g\right)\)
\(\Rightarrow M\text{ là }Na\)
\(\Rightarrow CTHH\text{ muối }:Na_2SO_4\)
