Answer:
2:1
Explanation:
The first step in this type of question is ensure yourself that the chemical is balanced. After establishing that, you read off the answer from the stoichiometric coefficients (the numbers in front of the formula) of potassium bromide and bromine and write those as the ratio, the molar ratio to be more specific.
It’s neutral with a pH of 7. It’s probably water.
C, the one with the most neutrons
Depending how you round and if you’re counting sig figs, it could be 28.8 or 29