Respuesta :
1) is the answer because the only way to turn it from blue to yellow is to mix it with an acidic solution.
The solution that when mixed with a drop of bromthymol blue will change the indicator to yellow is A. 0.1 M HCl.
What is an indicator?
An indicator simply means a substance that has measurable and observable characteristics that is important to depict an acidic or alkaline substance.
In this case, the solution that when mixed with a drop of bromthymol blue will change the indicator to yellow is 0.1 M HCl.
Learn more about indicators on:
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