Calculate the molality of a 2.50 molarity NaCl solution. Density of solution = 1.08 g/ml.
Density = 1.08 g/mL.
1000 mL has a mass of
1000 mL x 1.08 mL = 1080 grams.
2.50 moles NaCl has what mass?
2.50 x 58.5 (you need to be more accurate--this is just a quick guess) = 146 grams.
What is the mass of the water?
1080 mass water + 2.50 moles NaCl.
-146 g NaCl
difference is 934 g H2O.
So molality = 2.50 mols/0.934 kg solvnt = 2.68 m.
Check my thinking.Check my arithmetic.
I believe the density of water is 1 g/ml
Well, it seems like this question is really salt-y! To calculate the molality (you know, like molar concentration but with an "a" instead of an "o"), we need to know the mass of the solvent.
Since you already gave us the density of the solution, let's use that to find the mass.
Density is defined as mass divided by volume, so we can rearrange that equation to find the mass:
Mass = Density x Volume
The density you provided is 1.08 g/ml, and since we don't have the volume of the solution, we can assume it's 1 liter for the sake of simplicity (since 1 ml = 1 cm³).
Mass = 1.08 g/ml x 1000 ml = 1080 g
Now that we have the mass of the solution, we can calculate the molality using the equation:
Molality = Moles of solute / Mass of solvent (in kg)
Given that the molarity of the NaCl solution is 2.50 M (which means you have 2.50 moles of NaCl per liter of solution), and the mass of the solvent is 1080 g (which is equal to 1.080 kg), we can solve for molality.
Molality = 2.50 moles / 1.080 kg ≈ 2.315 mol/kg
So, the molality of the 2.50 M NaCl solution is approximately 2.315 mol/kg. Hope this salt-ifies your thirst for knowledge!
To calculate the molality (m) of a solution, we need to know the number of moles of solute (NaCl) dissolved per kilogram of solvent.
Given information:
Molarity (M) = 2.50 M
Density of solution (ρ) = 1.08 g/ml
Step 1: Calculate the moles of NaCl in the solution.
To convert from molarity (M) to moles, we need the volume of the solution.
Since we don't have the volume of the solution, we cannot directly calculate the moles of NaCl. However, since we know the density of the solution, we can indirectly find the volume.
Step 2: Calculate the volume of the solution.
We can calculate the volume of the solution by using the density and mass of the solution.
The density is given as 1.08 g/ml, and since the solution is in grams, we can assume the mass and volume are the same.
Mass of solution = Density of solution x Volume of solution
Mass of solution = 1.08 g/ml x 1000 ml
Mass of solution = 1080 g
Therefore, the volume of the solution is 1000 ml or 1 L.
Step 3: Calculate the moles of NaCl.
We can now calculate the moles of NaCl using the given molarity and volume of the solution.
Moles of NaCl = Molarity x Volume of solution (in liters)
Moles of NaCl = 2.50 M x 1 L
Moles of NaCl = 2.50 mol
Step 4: Calculate the molality.
Molality (m) is defined as the moles of solute divided by the mass of the solvent (in kilograms).
The mass of the solvent can be calculated by subtracting the mass of the solute (NaCl) from the total mass of the solution.
Mass of solvent = Mass of solution - Mass of solute
Mass of solvent = 1080 g - 2.50 mol x 58.44 g/mol
Mass of solvent = 1080 g - 146.10 g
Mass of solvent = 933.90 g
Therefore, the molality (m) of the 2.50 M NaCl solution is:
m = Moles of NaCl / Mass of solvent (in kg)
m = 2.50 mol / 0.93390 kg
m = 2.68 mol/kg
Therefore, the molality of the NaCl solution is 2.68 mol/kg.
To calculate the molality of a solution, you need to know the mass of the solute (NaCl) and the mass of the solvent (water).
First, convert the density of the solution to grams per milliliter. Since the density is given as 1.08 g/ml, the mass of the solution is 1.08 grams for every 1 milliliter.
Next, determine the volume of the solution for which the molarity is given. Since the molarity is given as 2.50 M, this means there are 2.50 moles of NaCl in 1 liter (1000 milliliters) of solution. So, the volume of the solution is 1000 ml.
Now, you can calculate the mass of NaCl in the solution. The molarity (M) of a solution is defined as moles of solute per liter of solution. Therefore, the number of moles of NaCl in the solution can be calculated by multiplying the molarity by the volume in liters:
moles of NaCl = molarity * volume (in liters)
= 2.50 M * 1 L
= 2.50 moles
Since the molarity is given as 2.50 M, this means there are 2.50 moles of NaCl in 1 liter (1000 milliliters) of solution.
Now, to calculate the mass of NaCl in the solution, you need to convert the volume of the solution to grams using the density. Since the density is given as 1.08 g/ml, you can convert the volume in milliliters to grams by multiplying by the density:
mass of solution = volume of solution * density
= 1000 ml * 1.08 g/ml
= 1080 grams
Since the density is given as 1.08 g/ml, this means that the mass of the solution is 1.08 grams for every 1 milliliter. Therefore, 1000 ml (1 liter) of solution has a mass of 1080 grams.
Now, you can calculate the molality using the equation:
molality = moles of solute / mass of solvent (in kg)
The mass of the solvent is equal to the mass of the solution minus the mass of the solute:
mass of solvent = mass of solution - mass of solute
= 1080 g - 2.50 mol * (58.44 g/mol)
= 1080 g - 146.1 g
= 933.9 g
The molecular weight of NaCl is 58.44 g/mol. Therefore, the mass of the solute (NaCl) is 2.50 moles multiplied by the molecular weight.
Finally, you can calculate the molality using the equation:
molality = 2.50 mol / (933.9 g / 1000 g/kg)
= 2.67 mol/kg
Therefore, the molality of the 2.50 molarity NaCl solution is 2.67 mol/kg.