Question

Chemicals can be classified as acidic, neutral, or basic, depending on their \(\mathrm{pH}\) measurements. \(\mathrm{A} \mathrm{pH}\) below 7 indicates that a substance is acidic, a \(\mathrm{pH}\) of 7 means that a substance is neutral, and a pH above 7 means that a substance is basic. An indicator is a chemical compound that, when added to a substance, changes color based on the \(\mathrm{pH}\) of the solution. For example, cabbage juice is an indicator that turns blue when added to a basic substance. $$ \begin{array}{|l|l|} \hline \text { Liquid } & \text { pH } \\ \hline \text { apple juice } & 3 \\ \hline \text { water } & 7 \\ \hline \text { acid rain } & 5 \\ \hline \text { ammonia } & 11 \\ \hline \end{array} $$ Based on the information and the table above, which of the following substances, if combined with cabbage juice, would cause the cabbage juice to turn blue? A. apple juice and acid rain B. water C. acid rain D. ammonia

Short answer

The correct answer is D. Ammonia, as it is the only basic substance in the table with a pH value above 7, which would cause the cabbage juice to turn blue.

Step-by-step solution

Identify basic substances

Based on the pH values provided in the table, we can label each substance as acidic, neutral, or basic: - Apple juice: pH 3, acidic - Water: pH 7, neutral - Acid rain: pH 5, acidic - Ammonia: pH 11, basic

Select the substance that will turn cabbage juice blue

As mentioned in the exercise, cabbage juice will turn blue when added to a basic substance. Based on our classification in Step 1, the only basic substance in the table is ammonia. Therefore, the correct answer is D. Ammonia.