how many grams of cacl2 are needed to prepare 6.00L of a 0.400M CaCl2 solution
How many moles do you want? That's M x L = ?
Then mols = grams/molar mass. YOu know molar mass and mols, solve for grams.
To calculate the number of grams of CaCl2 needed to prepare a certain volume and concentration of solution, you can use the formula:
moles = concentration x volume
In this case, the concentration of the CaCl2 solution is given as 0.400 M (moles per liter), and the volume is 6.00 L.
Step 1: Convert the volume from liters to milliliters.
6.00 L = 6000 mL
Step 2: Calculate the moles of CaCl2.
moles = concentration x volume
moles = 0.400 mol/L x 6000 mL / 1000 mL/L
moles = 2.4 mol
Step 3: Calculate the molar mass of CaCl2.
Ca: atomic mass = 40.08 g/mol
Cl: atomic mass = 35.45 g/mol
Molar mass of CaCl2 = 40.08 g/mol + 2 * 35.45 g/mol
Molar mass of CaCl2 = 40.08 g/mol + 70.90 g/mol
Molar mass of CaCl2 = 110.98 g/mol
Step 4: Calculate the grams of CaCl2 needed.
grams = moles x molar mass
grams = 2.4 mol x 110.98 g/mol
grams = 266.35 g
Therefore, to prepare 6.00 L of a 0.400 M CaCl2 solution, you would need 266.35 grams of CaCl2.