a sucrose solution was prepared by dissolving 13.5g sucrose in enough water to make 100ml of solution. the density is 1.050gml. calculate molality
13.5 g sucrose/molar mass = moles
convert 100 mL to mass.
mass = volume x density
mass = 100 mL x 1.050 g/mL = ??g and convert to kg.
Then molality = moles/kg solvent.
how do i get the mole fraction?
To calculate the molality of the sucrose solution, we need to know the moles of solute (sucrose) and the mass of the solvent (water).
1. First, we need to calculate the moles of sucrose in the solution.
To calculate the moles of sucrose, we use the formula:
moles = mass / molar mass
The molar mass of sucrose (C12H22O11) is:
12.01 g/mol (C) + 1.01 g/mol (H) + 16.00 g/mol (O) x 11 = 342.3 g/mol
So, the moles of sucrose can be calculated as:
moles = 13.5 g / 342.3 g/mol
moles = 0.03944 mol (rounded to 5 decimal places)
2. Next, we need to calculate the mass of water in the solution.
The density of the solution is given as 1.050 g/ml. Since the volume of the solution is 100 ml, we can calculate the mass of the solution using the formula:
mass = volume x density
So, the mass of the solution can be calculated as:
mass = 100 ml x 1.050 g/ml
mass = 105 g
3. Now, we need to determine the mass of the solvent (water) in the solution.
The mass of the solvent (water) can be calculated by subtracting the mass of the solute (sucrose) from the mass of the solution:
mass of solvent = mass of solution - mass of solute
mass of solvent = 105 g - 13.5 g
mass of solvent = 91.5 g
4. Finally, we can calculate the molality using the formula:
molality = moles of solute / mass of solvent (in kg)
First, we need to convert the mass of solvent from grams to kilograms:
mass of solvent = 91.5 g / 1000 (1 kg = 1000 g)
mass of solvent = 0.0915 kg
Now we can calculate the molality:
molality = 0.03944 mol / 0.0915 kg
molality ≈ 0.431 mol/kg (rounded to 3 decimal places)
Therefore, the molality of the sucrose solution is approximately 0.431 mol/kg.
To calculate the molality of a solution, we need to know the moles of solute (in this case, sucrose) present in the solution and the mass of the solvent (in this case, water) in kilograms.
First, let's start by calculating the moles of sucrose in the solution.
The molar mass of sucrose (C12H22O11) can be calculated as follows:
(12.01 g/mol x 12) + (1.008 g/mol x 22) + (16.00 g/mol x 11) = 342.30 g/mol
Next, we can calculate the moles of sucrose by dividing the given mass by the molar mass:
moles of sucrose = 13.5 g ÷ 342.30 g/mol
Now, let's calculate the mass of water in kilograms. We have 100 mL of solution, and the density is given as 1.050 g/mL. So, the mass of the solution can be calculated as:
mass of solution = volume of solution x density
mass of solution = 100 mL x 1.050 g/mL
Since the density is given in grams per milliliter, the mass of water in the solution is equal to the mass of the solution.
Finally, we need to convert the mass of water from grams to kilograms by dividing by 1000:
mass of water = mass of solution ÷ 1000
Now that we have the moles of sucrose and the mass of water in kilograms, we can calculate the molality using the formula:
molality (m) = moles of solute ÷ mass of solvent (in kilograms)
Let's substitute the values we calculated into the formula:
molality = moles of sucrose ÷ mass of water (in kilograms)
Please calculate the moles of sucrose and the mass of water in kilograms, and then substitute those values into the formula to find the molality.