Answer:
Bromine loses an electron.
Step-by-step explanation:
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In this case, according to the given chemical reaction, it will be possible for us to realize that as the reaction progresses, we see that the bromine, as it is initially negative, it increases the oxidation state as it loses an electron for which it is oxidized.
Moreover, no change is potassium is evidenced as it remains as the cation in the reaction; therefore, the answer is Bromine loses an electron.
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