You would want to make sure that you have controlled the variables properly, and if you determine that you did then you would repeat the experiment to be sure of the results.
Answer:
Element Symbol Mass Percent
Cuprum Cu 66.464%
Sulfur S 33.537%
Explanation:
I got this out of my module, sorry if it's wrong but i am pretty sure 97% this is correct!
The reaction would be Exothermic
Answer: Potassium
Explanation: Potassium is the chemical element with 19 electrons, 19 protons and 20 neutrons.
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