The full chemical symbol for an element<span> shows its mass </span>number<span> at the top, and its atomic </span><span>number at the bottom</span>
Answer:
a reactant is a substance that is at the beginning of a Chemical reaction while a product is a substance that is present at the end of a chemical reaction.in other words a reactant is a substance used up in a chemical reaction to produce something while a reactant is what is produced after a chemical reaction.
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