Uploaded April 2020 | Updated September 2026, 2 weeks ago
In this demonstration, two methods for synthesising carbon dioxide are explained. The first method involves the reaction between a metal carbonate and a dilute acid. The second method involves the thermal decomposition of a metal carbonate, in this case copper(II) carbonate.
In the second demonstration, notice the colour change as green copper(II) carbonate transforms into black copper(II) oxide.
The production of carbon dioxide is confirmed by bubbling the resulting gas through limewater (calcium hydroxide solution). Initially colourless, this turned cloudy on exposure to carbon dioxide: the product is an insoluble white solid called calcium carbonate. If excess carbon dioxide is used, soluble calcium hydrogen carbonate is formed and the solution reverts to colourless. This begins to occur at the end of both demonstrations.
In this demonstration, two methods for synthesising carbon dioxide are explained. The first method involves the reaction between a metal carbonate and a dilute acid. The second method involves the thermal decomposition of a metal carbonate, in this case copper(II) carbonate.
In the second demonstration, notice the colour change as green copper(II) carbonate transforms into black copper(II) oxide.
The production of carbon dioxide is confirmed by bubbling the resulting gas through limewater (calcium hydroxide solution). Initially colourless, this turned cloudy on exposure to carbon dioxide: the product is an insoluble white solid called calcium carbonate. If excess carbon dioxide is used, soluble calcium hydrogen carbonate is formed and the solution reverts to colourless. This begins to occur at the end of both demonstrations.
