What is the molarity of a solution containing 18.0g of KCl in 262mL of KCl solution?
mols = grams KCl/molar mass KCl
Then M = mols KCl/L solution.
To find the molarity of the solution, we need to divide the number of moles of solute (KCl) by the volume of the solution in liters.
First, we need to find the number of moles of KCl. To do this, we use the formula:
moles = mass / molar mass
The molar mass of KCl is the sum of the atomic masses of potassium (K) and chlorine (Cl), which is approximately 39.10 g/mol (for K) + 35.45 g/mol (for Cl) = 74.55 g/mol.
moles = 18.0 g / 74.55 g/mol ≈ 0.2415 mol
Next, we need to convert the volume of the solution from milliliters (mL) to liters (L). We can do this by dividing the volume by 1000:
volume = 262 mL / 1000 = 0.262 L
Now we can find the molarity by dividing the number of moles by the volume in liters:
molarity = moles / volume
molarity = 0.2415 mol / 0.262 L ≈ 0.923 M
Therefore, the molarity of the solution containing 18.0g of KCl in 262mL of KCl solution is approximately 0.923 M.