Using molality and molarity to describe a solution Calculate the percent concentration of 125mg CuSO4 dissolved in enough water to make 5.00ml of solution
To calculate the percent concentration, we need to know the amount of CuSO4 in the solution and the total volume of the solution.
First, let's convert the given mass of CuSO4 to moles. The molar mass of CuSO4 is:
CuSO4 = 63.55 + 32.06 + 4(16.00) = 159.60 g/mol
125 mg CuSO4 = 125/1000 g CuSO4 = 0.125 g CuSO4
0.125 g CuSO4 x (1 mol CuSO4/159.60 g CuSO4) = 0.000783 mol CuSO4
Now, we need to find the total volume of the solution. We are given that 125 mg CuSO4 is dissolved in enough water to make 5.00 ml of solution.
The solution density is not given, but we can assume that the density of the solution is 1.00 g/mL. This means that the total mass of the solution is:
5.00 mL x 1.00 g/mL = 5.00 g
Now, we can convert the amount of CuSO4 to percent concentration:
Percent concentration = (amount of CuSO4 / total mass of solution) x 100%
Percent concentration = (0.000783 mol CuSO4 x 159.60 g/mol / 5.00 g) x 100%
Percent concentration = 2.50%
Therefore, the percent concentration of 125 mg CuSO4 dissolved in enough water to make 5.00 mL of solution is 2.50%.
To find the percent concentration of the CuSO4 solution, we need to determine the amount of CuSO4 in grams and the total mass of the solution. We can then use the formula:
Percent Concentration = (mass of solute / mass of solution) x 100
Given:
Amount of CuSO4 = 125 mg
Volume of solution = 5.00 mL
Step 1: Convert the mass of CuSO4 from milligrams (mg) to grams (g)
1 g = 1000 mg
125 mg = 0.125 g
Step 2: Determine the total mass of the solution
We need to convert the volume of the solution from milliliters (mL) to grams (g) using the density of water. The density of water is approximately 1 g/mL.
Mass of water = volume of solution x density of water
Mass of water = 5.00 mL x 1 g/mL
Mass of water = 5.00 g
Step 3: Calculate the percent concentration
Percent Concentration = (mass of CuSO4 / total mass of solution) x 100
Percent Concentration = (0.125 g / (0.125 g + 5.00 g)) x 100
Percent Concentration = (0.125 g / 5.125 g) x 100
Percent Concentration ≈ 2.44%
Therefore, the percent concentration of the CuSO4 solution is approximately 2.44%.
To calculate the percent concentration of a solution using molality and molarity, we first need to convert the given information into the appropriate units.
1. Convert 125mg to grams:
Since 1g = 1000mg, then 125mg = 0.125g.
2. Convert the volume of the solution from milliliters (ml) to liters (L):
Since 1L = 1000ml, then 5.00ml = 5.00/1000 = 0.005L.
Now we can proceed with the calculations using molality and molarity.
Molality (m) is defined as the amount of solute (in moles) divided by the mass of the solvent (in kilograms):
m = moles of solute / mass of solvent (in kg)
Molarity (M) is defined as the amount of solute (in moles) divided by the volume of the solution (in liters):
M = moles of solute / volume of solution (in L)
We can calculate both the molality and molarity using the given information:
1. Molality (m):
First, we need to calculate the moles of CuSO4.
The molar mass of CuSO4 is 63.55 g/mol (Cu: 63.55 g/mol, S: 32.07 g/mol, O: 16.00 g/mol x 4).
Moles of CuSO4 = mass (in grams) / molar mass
= 0.125g / 159.609g/mol = 0.00078355 mol
Now, we need to calculate the mass of the solvent, which is water in this case.
Mass of water = volume of solution x density of water
= 0.005L x 1000g/L = 5g
Finally, we can calculate the molality:
molality (m) = moles of CuSO4 / mass of solvent (in kg)
= 0.00078355 mol / 0.005kg = 0.15671 mol/kg
2. Molarity (M):
We have already calculated the moles of CuSO4 (0.00078355 mol), and we know the volume of the solution (0.005L).
So, we can calculate the molarity directly:
molarity (M) = moles of CuSO4 / volume of solution (in L)
= 0.00078355 mol / 0.005L = 0.15671 M
Now, let's calculate the percent concentration:
Percent concentration = (mass of CuSO4 / total mass of solution) * 100
Since the mass of CuSO4 is given as 125mg (which we already converted to grams), we need to find the total mass of the solution. The total mass of the solution is the sum of the mass of CuSO4 and the mass of the solvent (water).
Total mass of solution = mass of CuSO4 + mass of solvent
= 0.125g + 5g = 5.125g
Finally, we can calculate the percent concentration:
Percent concentration = (0.125g / 5.125g) * 100
≈ 2.44%
Therefore, the percent concentration of the CuSO4 solution is approximately 2.44%.