Question

imagine that small pieces of the metals copper, magnesium and iron are placed in three test tubes labeled A, B, and C, respectively. If enough aqueous HCl is added to each tube to completely submerge the metal pieces, predict the products that will form in each test tube

Answer 1

A) Cu

Cu + 2HCl --> CuCl2 + H2(g)

Products predicted: Copper(II) choloride and hydrogen gas


B) Mg

Mg + 2HCl --> MgCl2 + H2

Products predicted: magnesium chloride + hygrogen gas

C) Fe

Fe +2 HCl -> FeCl2 + H2, or
2Fe +6 HCl -> 2FeCl3 + 3H2

Products predicted: Iron(II) chloride, iron (III) chloride and hydrogen gas.

Answer 2

Test tube A will have bubbles form slowly and the Copper piece will dissolve slowly. The products will be Hydrogen gas and Copper Chloride salt, resulting in a blue solution.

Test tube B will have a violent reaction and bubbles will be produced very fast. The products will be Hydrogen gas and Magnesium Chloride salt. The solution will be colorless.

Test tube C will have bubbling as well and Hydrogen gas will be produced alongside Iron Chloride salt, giving the solution a dark green color.