Answer:
a metal and a nonmetal element
Explanation:
Answer:Student 2
Explanation:
Student 2 repeated the experiment several times with different seeds to make sure the experiment would come out with the same answers and was reliable, using the same area would make sure the environment wouldn't interfere. The other students didn't do all the things that student 2 needed for the experiment.
Word equation - calcium + oxygen -> calcium oxide
Chemical equation - Ca + O2 -> CaO2
Hope this helps!