Question

bromothymol blue is an indicator that changes colour at different ph levels.
bromothymol blue will appear yellow when mixed with
a. lemon juice
b. baking soda
c. drain cleaner
d. distilled water

Explanation:

To determine when bromothymol blue appears yellow, we refer to the table: it's yellow when pH is below 6 (acidic).

• Lemon juice is acidic (pH < 6), so bromothymol blue would be yellow.
• Baking soda is basic (pH > 7), drain cleaner is strongly basic, and distilled water is neutral (pH ≈ 7). So only lemon juice fits.

Answer:

A. lemon juice