Mario places 10 mL of water in a test tube and heats the liquid over a Bunsen burner for 2 minutes. After removing the test tube
from the Bunsen burner, there are 6 mL of water left in the test tube. This experiment is a good example of a A. chemical change involving chemical reactions. B. physical change involving chemical reactions. C. physical change involving phase changes. D. chemical change involving phase changes.
The answer is each indicator has a narrow range. We need many different indicators to span the entire ph spectrum because each indicator has a narrow range.
