How do you get bromophenol blue to change to yellow

t changes from yellow at pH 3.0 to blue at pH 4.6; this reaction is reversible. Bromophenol blue is structurally related to phenolphthalein (a popular indicator).

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Acid–base indicator.

Bromophenol blue (pH indicator)

below pH 3.0  above pH 4.6

Explanation:

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )

since electrons are negative the answer is neagtaive