How many grams of potassium chloride are produced if 4.00 g of nickel (III) chloride are reacted in this eqtn?

Convert mass of NiCl3 to moles: Nickel has a mass of 58.69 g/mol, and chlorine has a mass of 35.45g/mol - and there are 3 of them - so the mass due to chlorine is 3 x 35.45 = 106.35. The molar mass of NiCl3 is 58.69 + 106.35 = 165.04. So, with 4 g, you 4.00/165.04 = 0.02423 mol. The ratio between NiCl3 and KCl should be 1:3 (otherwise, you have three chloride ions in the reactants, but only one in the products). If this is the case, multiply 0.02423 x 3 = 0.07271 mol. To convert back to mass, multiply by the molar mass of KCl, 39.10 (K) + 35.45 (Cl) = 74.55 g/mol, to get the final answer: 0.07271 x 74.55 = 5.42 g. So the answer would be b).