The solubility of KI in ethyl alcohol is 2.00 grams of KI in 100.0 grams of this alcohol. From this information, calculate the molarity of this solution.
Can't do it. You can calculate molality but not molarity. If you have density you can convert molality to molarity.
To calculate the molarity of the solution, we need to know the volume of the solution in liters. We can find the volume of the solution by using the density of ethyl alcohol, which is approximately 0.79 g/mL.
First, we convert the given mass of ethyl alcohol to volume:
Mass of ethyl alcohol = 100.0 grams
Density of ethyl alcohol = 0.79 g/mL
Volume of ethyl alcohol = Mass of ethyl alcohol / Density of ethyl alcohol
Volume of ethyl alcohol = 100.0 g / 0.79 g/mL
Volume of ethyl alcohol = 126.58 mL
Next, we need to convert the volume of ethyl alcohol from milliliters to liters:
Volume of ethyl alcohol = 126.58 mL * (1 L / 1000 mL)
Volume of ethyl alcohol = 0.12658 L
Now that we have the volume of the solution in liters, we can calculate the molarity:
Molarity (M) = Moles of solute / Volume of solution (in liters)
We are given the mass of KI (solute) in grams, so we need to convert this to moles:
Mass of KI = 2.00 grams
Molar mass of KI = 39.10 g/mol + 126.9 g/mol = 166.0 g/mol (atomic masses of K and I)
Moles of KI = Mass of KI / Molar mass of KI
Moles of KI = 2.00 g / 166.0 g/mol
Moles of KI = 0.01205 mol
Finally, we can calculate the molarity:
Molarity (M) = 0.01205 mol / 0.12658 L
Molarity = 0.0952 M (rounded to four decimal places)
Therefore, the molarity of the solution is 0.0952 M.