What mass of potassium iodide is needed to prepare 5.60 L of a 1.13 M solution

Given that the question gives us concentration (M) and volume, we can use these so get moles. remember that Molarity (M) = mol / Liters, so if we want the moles, then

moles = M x L

moles = 1.13 x 5.60 = 6.33 moles KI

now to get the mass in grams, we need the molar mass of potassium iodide (KI) which can be determined using the periodic table and add the masses of each atom.

molar mass KI = 39.1 + 127 = 166.1 g/mol

6.33 mol (166 g / 1 mol) = 1050 grams KI