<span>Answer: an element and a compound.
An element is a pure substance formed by one kind of atoms (element).
A compound is a pure substance formed by several types of atoms(elements) that are connected by chemical bonds.
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Before an article is published in a scientific journal or in any "peer-reviewed" journal the article is reviewed thoroughly by scholars from the journal as well as peers or scholars of the articles author from the same field. This process occurs to provide credibility to the ideas being published and so that readers and other scholars can rely on the validity of the material being published.
Answer:
6 oxygens on the product side
Explanation:
1) balance the equation:
C2H4 + 3O2 → 2CO2 + 2H2O
2) calculate the number of oxygens on the product side
2CO2=4
2H2O=2