What is the molarity of a solution prepared by dissolving 2.41 g of potassium iodide, KI in 100 mL of water?
mols KI = grams/molar mass
M = mols/L soln.
To calculate the molarity of a solution, you need to know the number of moles of solute and the volume of the solution in liters.
1. First, you need to calculate the number of moles of potassium iodide (KI) in the solution. To do this, you can use the formula:
Moles = Mass / Molar mass
The molar mass of KI can be calculated by adding the atomic masses of one potassium atom (K) and one iodine atom (I) together. The atomic masses can be found from the periodic table.
Molar mass of KI = Atomic mass of K + Atomic mass of I
2. Next, convert the volume of the solution from milliliters (mL) to liters (L). Since 1 L is equal to 1000 mL, divide the volume by 1000:
Volume (in L) = Volume (in mL) / 1000
3. Finally, use the formula for molarity:
Molarity = Moles / Volume (in L)
Plug in the values you calculated to find the molarity of the solution.
Now, let's follow these steps to find the molarity of the KI solution.
1. Calculate the molar mass of KI:
Atomic mass of K = 39.10 g/mol
Atomic mass of I = 126.90 g/mol
Molar mass of KI = Atomic mass of K + Atomic mass of I
2. Calculate moles of KI:
Moles = Mass / Molar mass
Moles = 2.41 g / Molar mass of KI (g/mol)
3. Convert the volume of the solution from mL to L:
Volume (in L) = 100 mL / 1000
4. Calculate the molarity of the solution:
Molarity = Moles / Volume (in L)
Molarity = Moles / Volume (in L)
By following these steps, you should be able to find the molarity of the KI solution.