A solution contains 5.00g of urea per 0.100kg of water (COCNH2)2 if the vapour pressure of pure water at 25°c is 23.7ton. What is the vapour pressure of the solution
Am not convinced
To determine the vapor pressure of the solution, we need to use Raoult's Law, which states that the vapor pressure of a solution is equal to the mole fraction of the solvent multiplied by the vapor pressure of the pure solvent.
First, we need to calculate the mole fraction of water in the solution. We can use the formula:
Mole Fraction of Water (Xwater) = mass of water / (mass of water + mass of urea)
Given:
mass of water = 0.100 kg
mass of urea = 5.00 g = 0.005 kg
Xwater = 0.100 kg / (0.100 kg + 0.005 kg) = 0.100 kg / 0.105 kg = 0.9524
Next, we multiply the mole fraction of water by the vapor pressure of pure water to find the vapor pressure of the solution.
Vapor Pressure of Solution (Psolution) = Xwater * vapor pressure of pure water
Psolution = 0.9524 * 23.7 ton
Please note that "ton" is not a valid unit for vapor pressure. The correct unit for vapor pressure is usually "atm," "mmHg," or "Pa." Please specify the unit you would like the answer in, and I can provide the final calculation.
To find the vapor pressure of the solution, we need to use 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 pure solvent. The mole fraction of the solvent is the ratio of moles of solvent to the total moles of the solution.
First, let's calculate the moles of urea and water in the solution:
The mass of urea in the solution is given as 5.00 g.
The molar mass of urea (COCNH2)2 is approximately 60.06 g/mol.
Moles of urea = mass of urea / molar mass of urea
= 5.00 g / 60.06 g/mol
≈ 0.0832 mol
The mass of water in the solution is given as 0.100 kg.
The molar mass of water (H2O) is approximately 18.015 g/mol.
Moles of water = mass of water / molar mass of water
= 0.100 kg × 1000 g/kg / 18.015 g/mol
≈ 5.55 mol
Next, let's calculate the mole fraction of water:
Mole fraction of water = moles of water / total moles of the solution
= 5.55 mol / (0.0832 mol + 5.55 mol)
≈ 0.985
Now, we can find the vapor pressure of the solution:
Vapor pressure of the solution = mole fraction of water × vapor pressure of pure water at 25 °C
= 0.985 × 23.7 torr
≈ 23.3 torr
Therefore, the vapor pressure of the solution is approximately 23.3 torr.
mols urea = grams/molar mass = ?
mols H2O = 100 g/molar mass = ?
Total mols = nurea + nH2O
mole fraction H2O = XH2O
XH2O = nH2O/total mols
psolution = XH2O*PoH2O