Calculate the molarity of each of the following solutions. 12.03mg KI in 107.6mL of solution.Express your answer using four significant figures.
Molarity is moles/liter
You have to find moles: 12.03 mg/molecular weight of KI watch your units because you have mg instead of grams.
Once you have your number of moles divide that by 107.6 and set equal to ? moles/1000 ml.
To calculate the molarity (M) of a solution, we need to know the amount of solute (in moles) and the volume of the solution (in liters). The formula for calculating molarity is:
Molarity (M) = moles of solute / volume of solution (in liters)
First, we need to convert the given mass of solute (in milligrams) to moles. The molar mass of KI (potassium iodide) is 166.00 g/mol.
1. Convert mass from mg to g:
12.03 mg = 0.01203 g
2. Convert mass from grams to moles:
moles of KI = mass of KI (in grams) / molar mass of KI
moles of KI = 0.01203 g / 166.00 g/mol
moles of KI = 0.00007259 mol
Next, we need to convert the given volume of the solution (in milliliters) to liters.
1. Convert volume from mL to L:
107.6 mL = 0.1076 L
Now we have the moles of KI (0.00007259 mol) and the volume of the solution in liters (0.1076 L). We can use these values to calculate the molarity.
Molarity (M) = moles of solute / volume of solution (in liters)
Molarity (M) = 0.00007259 mol / 0.1076 L
Calculating this value gives us:
Molarity (M) = 0.000674 M
Therefore, the molarity of the solution containing 12.03 mg of KI in 107.6 mL of solution is 0.000674 M.