Making Soluble Salts & Electrolysis
Salt-making is all about combining positive ions (from metals or metal compounds) with negative ions to create new compounds. You'll use copper oxide and sulfuric acid as your limiting reactant to make beautiful blue copper sulfate crystals.
The trick is heating your acid gently, then adding copper oxide bit by bit until there's powder left over - this tells you the reaction has stopped and your solution is neutral. After filtering out the excess powder, you'll evaporate half the water and wait 24 hours for crystals to form.
Electrolysis splits compounds using electricity and graphite electrodes. With copper chloride solution, you'll get copper coating the cathode (negative electrode) and chlorine gas bubbles at the anode. Sodium chloride behaves differently - you get hydrogen gas at the cathode instead because sodium is too reactive.
Top Tip: Always test gases safely - use damp litmus paper for chlorine and a lit splint for hydrogen. Never let your electrodes touch or you'll create a dangerous short circuit!
