mass soln = volume x density
%m/m = [g KCl/(g KCl + g solvent)]*100 =
M = mols/L soln.
mols = grams/molar mass. volume soln = 0.179L
What is the percent (m/m) for the potassium chloride solution?
What is the molarity, M, for the potassium chloride solution? need help pls
%m/m = [g KCl/(g KCl + g solvent)]*100 =
M = mols/L soln.
mols = grams/molar mass. volume soln = 0.179L
Step 1: Calculate the mass of KCl in the solution.
Mass of KCl = 4.60 g
Step 2: Calculate the total mass of the solution.
Density = mass/volume
mass = density * volume
mass = 1.11 g/mL * 179 mL
mass = 198.69 g
Step 3: Calculate the percent (m/m).
Percent (m/m) = (mass of KCl / total mass of solution) * 100
Percent (m/m) = (4.60 g / 198.69 g) * 100
Percent (m/m) ≈ 2.31%
Therefore, the percent (m/m) for the potassium chloride solution is approximately 2.31%.
Now let's find the molarity (M) for the potassium chloride solution.
Molarity (M) is defined as the number of moles of solute per liter of solution.
Step 1: Calculate the moles of KCl.
Moles of KCl = mass of KCl / molar mass of KCl
The molar mass of KCl can be calculated using the atomic masses of potassium (K) and chlorine (Cl).
Molar mass of KCl = atomic mass of K + atomic mass of Cl
Molar mass of KCl = 39.10 g/mol + 35.45 g/mol
Molar mass of KCl = 74.55 g/mol
Moles of KCl = 4.60 g / 74.55 g/mol
Moles of KCl ≈ 0.0617 mol
Step 2: Calculate the volume in liters.
Volume in liters = volume in mL / 1000
Volume in liters = 179 mL / 1000
Volume in liters = 0.179 L
Step 3: Calculate the molarity.
Molarity (M) = moles of KCl / volume in liters
Molarity (M) = 0.0617 mol / 0.179 L
Molarity (M) ≈ 0.344 M
Therefore, the molarity (M) for the potassium chloride solution is approximately 0.344 M.