In order to figure out how many grams of CaCl2 are contained in a liter, we must first consider how many grams are contained in a mole.
How many grams is 1 mole of CaCl2?
1 mole of CaCl2 is 1 mole of Ca and 2 moles of Cl
1 mole of Ca weighs 40 g, and 2 moles of Cl weighs roughly 35x2=70 grams.
Therefore, 1 mole of CaCl2 weighs about 110 grams. Consult a periodic table for more precise numbers (weight of 1 mole is the atomic mass).
There are 2 moles of CaCl2 per liter, so 1 liter contains 110 x 2 = 220 grams of CaCl2.
220grams/Liter * .250L = 55g/liter