Question

the empirical formula of a compound is NO2. it's molecular mass is 92g/mol. What is its molecular formula?

Answer 1

The molecular formula:

`N_x(O_2)_x`


`M_(N_x(O_2)_x)=x * M_N + x * 2 * M_O \\ \\ m_N=14 \ (g)/(mol) \\ m_O=16 \ (g)/(mol) \\ M_(N_x(O_2)_x)=92 \ (g)/(mol) \\ \\ 92=x * 14+x * 2 * 16 \\ 92=14x+32x \\ 92=46x \\ (92)/(46)=x \\ x=2 \\ \\ N_2(O_2)_2 \Rightarrow N_2O_4`

The molecular formula is N₂O₄.