A sample containing 7.45 grams of KCl is dissolved in sufficient distilled water and reacted with 1000.0 mL 0.300M AgNO3 solution. Excess silver nitrate solution reacted with the metallic copper according to the following reaction:
Cu (s) + 2 AgNO3 (aq) ---> Cu(NO3)2 (aq) + 2 Ag (s)
The precipitate is filtered off and a strip of copper weighing 10.00 grams is dropped into the filtrate. After the reaction is terminated, the mass of unreacted copper remaining is: ______