This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
1 mole of Cu is 63.55g Therefore we can make a mole relationship representing that:
1 mole Cu/63.55g Cu

0.42 mol Cu(63.55g Cu/1 mole Cu)=26.69g Cu

Therefore 0.42 mol Cu=26.69g Cu