`n_{O_2}={5,9496}/{24,79}=0,24(mol)`

`->m_{CO_2}+m_{H_2O}=0,24.32+7,2=14,88(g)`

`m_{CO_2}:m_{H_2O}=22:9`

`->m_{CO_2}=10,56(g);m_{H_2O}=4,32(g)`

BTNT C: `n_C=n_{CO_2}={10,56}/{44}=0,24(mol)`

BTNT H: `n_H=2n_{H_2O}=2.{4,32}/{18}=0,48(mol)`

`->n_O={7,2-0,24.12-0,48}/{16}=0,24(mol)`

`->n_C:n_H:n_O=0,24:0,48:0,24=1:2:1`

`->` CTN: `(CH_2O)_n`

`M_A=30n=6/{{4,4}/{44}}=60(g//mol)`

`->n=2`

`->A:C_2H_4O_2`

$n_{O_2}=\dfrac{5,9496}{24,79}=0,24(mol)\\ \xrightarrow{btkl:} m_A+m_{O_2}=m_{CO_2}+m_{H_2O}\\\to m_{CO_2}+m_{H_2O}=7,2+0,24.32=14,88(g)\\ m_{CO_2}=\dfrac{22.14,88}{22+9}=10,56(g)\\ m_{H_2O}=14,88-10,56=4,32(g)\\ \xrightarrow{btnt\ C:} n_C=n_{CO_2}=\dfrac{10,56}{44}=0,24(mol)\\ \xrightarrow{btnt\ H:} n_H=2n_{H_2O}=\dfrac{2.4,32}{18}=0,48(mol)\\ m_C+m_H=0,24.12+0,48=3,36<m_A\\ \to A\ chua\ C,H,O\\ n_O=\dfrac{7,2-3,36}{16}=0,24(mol)\\ n_C:n_H:n_O=0,24:0,48:0,24=1:2:1\\ \to A:(CH_2O)_n\\ M_A=\dfrac{6}{\frac{4,4}{44}}=60(g/mol)\\ M_A=(12+1.2+16)n=60(g/mol)\\\to n=2\\ A: C_2H_4O_2$