posted by Help please! on .
a coin is composed of gold and silver. the 5.00g coin is dissolved in nitric acid and the solution treated with NaCl to precipitate out 2.35g of AgCl. Gold chlorides do not precipitate under the same conditions.
What is the composition of silver (by mass) in this coin?
Two or three things I want to point out to you. First, note the correct spelling of chemistry. Second, Au is NOT soluble in HNO3 alone. That's why Au is called a noble metal and it requires aqua regia (royal water) to dissolve it. Aqua regia is a mixture of HNO3 and HCl. For the problem:
Convert 2.35g AgCl to g Ag (find percent Ag in AgCl) and %Ag(as a fraction) x 2.35 = g Ag.
%Ag = (g Ag/g sample)*100 =