Here are the enthalpy changes when one mole of HCl gas is added to various moles of water: -16.608 Kcal for 10 mol, -17.272 Kcal for 25 mol, -17.453 Kcal for 40 mol, -17.735 Kcal for 200 mol, -17.960 for infinte mol. Find the hear evolved when 1109.5 grams of 3 molal HCl is diluted to 0.3 molal HCl. How many grams of water must be added to make this dilution?