Using the instructions provided in Robert Bruce Thompson’s book Illustrated Guide to Home Chemistry Experiments, and having watched several YouTube videos on the subject, I set out in early 2015 to synthesise copper carbonate.
I began by weighing out 33 g of sodium bicarbonate (NaHCO3; from Woolies) into a plastic cup, then weighed out 50 g of copper sulfate (CuSO4; from Bunnings) into a jam jar. I added 218 g of tap water to the copper sulfate, stirred until it dissolved, then slowly added the bicarb while stirring well. The copper sulfate, which had been a deep clear blue colour, turned a cloudy lighter blue, and frothed up – dictating that only 5 g or so of bicarb could be added at a time.
After leaving it to sit for 10 minutes, the CuCO3 had precipitated out on the bottom of the jar, and there was a clear layer of liquid (containing sodium sulfate, NaSO4) on top. Occasional bubbles of carbon dioxide broke through the copper carbonate layer, and clung to the spoon or the sides of the jar.
I managed to extract most of the sodium sulfate water using a disposable Beral pipette, and ran it through some filter paper to remove any copper carbonate, then placed it in a plastic tray to dry. I also filtered the copper carbonate, and set it aside in a tray to dry. There was some sodium sulfate in with the copper carbonate, which I scraped off once it had dried.