Chemistry question

A The solution becomes a deeper orange.
B The colour of the solution becomes lighter.
C The solution goes colourless.
D The colour of the solution becomes darker.
E No visible change.

The answer is B. Can someone explain this question?

If we add Dil NaOH the OH- ions react with the Hydrogen in the products and thus the H+ conc decreases due to formation of water by the reaction of H+ and OH-. This by Le chatelier the reaction moves towards right as to counteract the decrease in H+ conc and thus the color lightens.

Hey thanks for the reply. However, I still have a question: why doesn’t it become colorless?

I think since the reaction is in equilibrium thus there will always be some concentration of Bromine Water to maintain the equilibrium and thus the solution won’t be colorless.

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