This is an oldie but a goodie as a lab on last day of class prior to Xmas break without doing any cooking or candy making in lab. You have students make a holiday ornament by plating some copper out on another metal.
Materials:
galvanized sheet metal from machine shop cut into 5x 5 cm squares with hole
drilled through at one of the corners; masking tape; pencil; utility knife;
steel wool; and copper(II) nitrate solution(about 0.1M) and 20 mL per student.
Procedure:
Polish both sides of metal with steel wool; cover both sides with masking
tape; draw diagram on masking tape(something in holiday spirit like snowflake)
and may draw on both sides; cut out the design to metal surface with utility
knife; dip the metal into copper(II) nitrate solution or dab with cotton
soaked in solution using tongs and rub onto bare metal but do not touch with
fingers; rinse ornament in water and allow to dry; remove excess tape; write
a chem equation for this reaction; and then hang your ornament on Xmas tree
each year as reminder of your chem experience.
An Alternate Procedure but more chemistry:
After cutting out design, dip in dilute HCl until bubbling stops then rinse
with water and dry with paper toweling; write chem equation for this reaction;
rub exposed area with eraser; do not remove tape; dip or swab exposed area
with copper(II) nitrate solution; write chem equation for this reaction;
rinse with water and dry; and remove tape.
Questions? Comments??
John R. Krikau