For this problem we need to define the molarity equation, then identify the missing pieces. Since we're looking at molarity, it's important to show the M = n/V, where n = number of moles and V = volume. If we substitute in the information we already have, the problem becomes 0.560M = Xmoles/1.50L, and we need to find Moles. I know the problem asks for grams, but we can get that once we get moles. Since we're given molarity, we have to work within that system to find the answer.
So, 0.560Moles/Liter = X/1.50Liter, to solve for X, it's just algebra. Multiply both sides by 1.50Liter to remove it from the bottom of the equation on the right. That gives us 0.84moles = X. So now we know that 0.84 moles are needed. Now you just need to convert that to grams.
To do that, find the molar mass of CuCl2 using a periodic table. It comes out to 134.45grams/mole. Then multiple the number of moles by the mass in order to do the conversion. So 0.84moles * 134.45g/mol = 112.938grams. Then we just need to check Sig Figs. It looks like there are 3 in the question, so we'll round that off to three. 113.grams. Done!
