Au is the symbol for gold. It comes from Latin word for gold, which is Aurunum. Its atomic number is 79.
A. add a catalyst is the correct answer.
A catalyst never takes part in the reaction, so it does not affect the reaction.
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Explanation:
here is the answer to your question
If this is balancing them its 4H+1NH —> 1H+NH4
The first one would be it