How Much Copper Must Be Added To $8.0 \mathrm{~kg}$ Of Pure Silver (Usually

Short Answer

How much copper must be added to $8.0 \mathrm{~kg}$ of pure silver (usually $99.9 \%$ pure, but use $100 \%$ for your calculations) in order to make a sterling silver alloy of $92.5 \%$ silver and $7.5 \%$ copper?