Learn chemistry and identify authenticity. Someone on the market used a 5 -corner coin (copper -zinc alloy) to make fake gold jewelry for cheating. Xiao Xiao used a reagent to expose him

By huanggs
Learn chemistry and identify authenticity. Someone on the market used a 5 -corner coin (copper -zinc alloy) to make fake gold jewelry for cheating. Xiao Xiao used a reagent to expose him. The reagent that Xiao Xiao must not use is () A. Copper sulfate solution B. C. Silver solution C. D. hydrochloric acid D. Sodium nitrate solution