How many grams of calcium chloride would you dissolve in water to make a total .111 M calcium chloride solution with 200 mL final volume?
mass=molmass*molarity*volumeinliters
To determine how many grams of calcium chloride you need to dissolve in water, you need to follow a few steps:
Step 1: Understand the problem
The problem states that you need to make a total of 0.111 M calcium chloride solution with a final volume of 200 mL.
Step 2: Calculate the number of moles
To calculate the number of moles, we need to use the molarity and volume of the solution. The equation is:
moles = molarity × volume (in liters)
First, convert the volume from milliliters to liters:
200 mL = 200/1000 = 0.2 L
Next, multiply the molarity by the volume to get the number of moles:
moles = 0.111 M × 0.2 L = 0.0222 moles
Step 3: Calculate the molar mass
The molar mass of calcium chloride (CaCl2) is the sum of the atomic masses of calcium (Ca) and chlorine (Cl):
molar mass of CaCl2 = (1 × atomic mass of Ca) + (2 × atomic mass of Cl)
The atomic masses of Ca and Cl are 40.08 g/mol and 35.45 g/mol, respectively. Therefore:
molar mass of CaCl2 = (1 × 40.08 g/mol) + (2 × 35.45 g/mol) = 110.98 g/mol
Step 4: Calculate the mass of calcium chloride
Now, use the number of moles and the molar mass to calculate the mass of calcium chloride:
mass = moles × molar mass = 0.0222 moles × 110.98 g/mol = 2.47 grams
Therefore, you would need to dissolve approximately 2.47 grams of calcium chloride in water to make a 0.111 M solution with a final volume of 200 mL.