Respuesta :
The number of moles is determined by the formula:
number of moles = [tex]\frac{given mass}{molar mass}[/tex]
Now determining the number of moles:
- [tex]CO_2[/tex]
Molar mass of [tex]CO_2[/tex] is [tex]44.01 g/mol[/tex]
[tex]\frac{0.138 g}{44.01 g/mol} = 0.00316 mol[/tex]
- [tex]C[/tex]
[tex]0.00316 mol CO_2\times \frac{1 mole of C}{1 mole of CO_2} = 0.00316 mol[/tex]
- [tex]H_2O[/tex]
Molar mass of [tex]H_2O[/tex] is [tex]18 g/mol[/tex]
[tex]\frac{0.0556 g}{18 g/mol} = 0.00309 mol[/tex]
-[tex]H[/tex]
[tex]0.00309 mol H_2O\times \frac{2 mole of H}{1 mole of H_2O} = 0.00618 mol[/tex]
- [tex]NH_3[/tex]
Molar mass of [tex]NH_3[/tex] is [tex]17.031 g/mol[/tex]
[tex]\frac{0.0238 g}{17.031 g/mol} = 0.00139 mol[/tex]
- [tex]N[/tex]
[tex]0.00139 mol NH_3\times \frac{1 mole of N}{1 mole of NH_3} = 0.00139 mol[/tex]
[tex]0.200 g[/tex] sample contains [tex]0.00139 mol[/tex]. So,
[tex]0.150 g[/tex] of sample contains:
[tex]\frac{0.150 g}{0.200 g}\times 0.00139 mol = 0.00104 mole N[/tex]
- [tex]AgCl[/tex]
Molar mass of [tex]AgCl[/tex] is [tex]143.321 g/mol[/tex]
[tex]\frac{0.125 g}{143.321 g/mol} = 0.00175 mol[/tex]
- [tex]Cl[/tex]
[tex]0.00175 mol AgCl\times \frac{1 mole of Cl}{1 mole of AgCl} = 0.00175 mol[/tex]
[tex]0.125 g[/tex] sample contains [tex]0.00175 mol[/tex]. So,
[tex]\frac{0.150 g}{0.125 g}\times 0.00175 mol = 0.0021 mole Cl[/tex]
Now writing the formula with their respective moles:
[tex]C_{0.00316}H_{0.00618}N_{0.00104}Cl_{0.00210}[/tex]
Dividing with the smallest value of moles:
[tex]C_\frac{{0.00316}}{0.00104}H_{\frac{0.00618}{0.00104}}N_\frac{0.00104}{0.00104}Cl_\frac{{0.00210}}{0.00104}[/tex]
[tex]C_3H_6NCl_2[/tex]
Hence, the empirical formula is [tex]C_3H_6NCl_2[/tex].
