A solution is prepared by dissolving 104.1 grams of barium chloride, BaCl2 in 1000. grams of water? What is the boiling point of this solution? [The boiling point elevation constant for water is 0.52°C/mole solute in 1000g of water]
mols BaCl2 = grams/molar mass = ?
molality = m = mols/kg solvent
delta T = i*Kb*m
i = 3 for BaCl2
Solve for delta T and add to the normal boiling point of water for the final b.p.
To find the boiling point of the solution, we need to consider the boiling point elevation caused by the presence of a solute in water.
The formula to calculate the boiling point elevation is:
ΔTb = Kb * m
Where:
ΔTb = Change in boiling point
Kb = Boiling point elevation constant for the solvent (water)
m = Molality of the solution
First, let's calculate the molality of the solution. Molality is defined as the number of moles of solute per kilogram of solvent.
Number of moles of barium chloride (BaCl2) = mass / molar mass
Molar mass of BaCl2 = (1 * atomic mass of Ba) + (2 * atomic mass of Cl)
= (1 * 137.33 g/mol) + (2 * 35.45 g/mol)
= 137.33 g/mol + 70.90 g/mol
= 208.23 g/mol
Number of moles of BaCl2 = 104.1 g / 208.23 g/mol
Now, we need to convert the mass of water to kilograms.
Mass of water = 1000 grams
Mass of water in kilograms = 1000 grams / 1000 = 1 kg
Now, we can calculate the molality:
Molality (m) = moles of solute / mass of solvent in kg
= (104.1 g / 208.23 g/mol) / 1 kg
Next, we need to calculate the change in boiling point (ΔTb) using the boiling point elevation constant for water (0.52°C/mole solute in 1000g of water).
ΔTb = Kb * m
= 0.52°C/mole * (104.1 g / 208.23 g/mol) / 1 kg
Finally, we have ΔTb, which is the change in boiling point. To find the boiling point of the solution, we need to add this to the boiling point of pure water. The normal boiling point of water is 100°C.
Boiling point of the solution = 100°C + ΔTb
Now you can solve the equation to find the boiling point of the solution.
To find the boiling point of the solution, we need to calculate the boiling point elevation caused by the dissolved barium chloride. The boiling point elevation (ΔTb) can be calculated using the formula:
ΔTb = Kb * m
Where:
- ΔTb is the boiling point elevation (in °C)
- Kb is the boiling point elevation constant for water (0.52°C/mole solute in 1000g of water)
- m is the molality of the solution, which can be calculated by dividing the moles of solute by the mass of the solvent (in kg).
First, let's find the molality (m):
Step 1: Calculate the moles of barium chloride (BaCl2)
Molar mass of BaCl2 = 137.33 g/mol (barium) + 2 * 35.45 g/mol (chlorine) = 208.23 g/mol
moles of BaCl2 = mass / molar mass
moles of BaCl2 = 104.1 g / 208.23 g/mol
Step 2: Convert the mass of water to kilograms.
mass of water = 1000 g = 1 kg
Step 3: Calculate the molality (m)
m = moles of BaCl2 / mass of water (in kg)
m = (104.1 g / 208.23 g/mol) / 1 kg
m = 0.500 mol / 1 kg
m = 0.500 mol/kg
Now, we can calculate the boiling point elevation (ΔTb):
ΔTb = Kb * m
ΔTb = 0.52°C/mole solute in 1000g of water * 0.500 mol/kg
ΔTb = 0.26°C
Finally, to find the boiling point of the solution, we add the boiling point elevation to the boiling point of pure water, which is 100°C:
Boiling point of the solution = boiling point of pure water + ΔTb
Boiling point of the solution = 100°C + 0.26°C
Therefore, the boiling point of the solution is 100.26°C.