Final answer:
The vapor pressure of an aqueous solution containing glucose can be calculated using Raoult's law. The vapor pressure of the solution at 45°C would be approximately 65.29 torr. If the glucose in the solution were substituted with an equivalent amount of NaCl, the vapor pressure would remain the same.
Step-by-step explanation:
The vapor pressure of an aqueous solution containing glucose can be calculated using Raoult's law. According to Raoult's law, the vapor pressure of a solution is equal to the mole fraction of the solvent multiplied by the vapor pressure of the solvent. At 25°C, the vapor pressure of pure water is 23.8 torr, and the vapor pressure of the solution is 21.6 torr. We can use these values to calculate the mole fraction of water in the solution.
Using the equation:
Ptotal = Psolvent × Xsolvent
where Ptotal is the total vapor pressure, Psolvent is the vapor pressure of the solvent, and Xsolvent is the mole fraction of the solvent. Rearranging the equation to solve for Xsolvent, we have:
Xsolvent = Ptotal / Psolvent
Substituting the given values, we get:
Xsolvent = 21.6 torr / 23.8 torr = 0.9076
This means that the mole fraction of water in the solution is 0.9076. To calculate the vapor pressure of the solution at 45°C, we can use the same equation and the vapor pressure of pure water at that temperature (71.9 torr):
Ptotal = Psolvent × Xsolvent
Substituting the values, we get:
Ptotal = 71.9 torr × 0.9076 = 65.29 torr
Therefore, the vapor pressure of the solution at 45°C would be approximately 65.29 torr.
If the glucose in the solution were substituted with an equivalent amount of NaCl, the vapor pressure would not change since NaCl is a non-volatile solute. The vapor pressure would still be approximately 65.29 torr at 45°C.