Answer:
The total vapor pressure is 84.29 mmHg
Explanation:
Step 1: Data given
Solution = 40.00 (v/v) % benzene in CCl4
Temperature = 20.00 °C
The vapor pressure of pure benzene at 20.00 °C = 74.61 mmHg
Density of benzene is 0.87865 g/cm3
The vapor pressure of pure carbon tetrachloride is 91.32 mmHg
We suppose the total volume = 100 mL
Step 2: Calculate volume benzene and CCl4
40 % benzene = 40 mL
60 % mL CCl4 = 60 mL
Step 3: Calculate mass benzene
Mass = density * volume
Mass of benzene = 40.00 mL * 0.87865 g/mL = 35.146 g
Step 4: Calculate moles of benzene
Moles = mass / molar mass
Number of moles of benzene = 35.146 grams / 78 g/mol = 0.45059 mol
Step 5: Calculate mass of CCl4
Mass of CCl4 = 60 mL * 1.5940 g/mL = 95.64 g
Step 6: Calculate moles CCl4
Number of moles of CCl4 = 95.64 grams / 154g/mol = 0.62104 mol
Step 7: Calculate total number of moles
Total number of moles = moles benzene + moles CCl4
0.45059 moles + 0.62104 moles = 1.07163 mol
Step 8: Calculate mole fraction benzene and CCl4
Mole fraction = moles benzene / total moles
Mole fraction of benzene = 0.45059 / 1.07163 = 0.4205
Mole fraction of CCl4 = 0.62104 / 1.07163 = 0.5795
Step 9: Calculate partial pressure
Partial pressure of benzene = 0.4205 * 74.61 = 31.37 mmHg
Partial pressure of CCl4 = 0.5795 * 91.32 = 52.92 mmHg
Total vapor pressure = 31.37 + 52.92 = 84.29 mmHg
The total vapor pressure is 84.29 mmHg
= 11.6 mol O₂