Question

what is the evidence that carbon has been produced in a reaction​

Answer 1

first you tell me what is the reaction.

Answer 2

Heya, mate this is what you need. Bubble the gas through limewater. The most effective way to test for CO2 is to bubble the gas through "limewater", a diluted solution of calcium hydroxide (slaked lime). When you bubble carbon dioxide through the solution, it forms a solid precipitate of calcium carbonate – chalk or limestone.

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