1.Chemicals in the air can combine with rain to produce acid rain, which is harmful to the environment. Which of these is most likely to be the pH of acid rain?

Question

A. 0
B. 4
C. 10
D. 14
2.Based on the materials measured in the Gizmo, what is the most likely pH of apple juice?
A. 0.3
B. 3.9
C. 8.4
D. 11.7
3.Suppose you have already compared the pH values of two substances using 0–14 paper. When would a follow-up test using 4.5–7.5 paper be most helpful?
A. when both substances had a pH value of about 3 on the 0–14 paper
B. when both substances had a pH value of about 6 on the 0–14 paper
C. when both substances had a pH value of about 9 on the 0–14 paper
D. when one substance had a pH value of about 5 and the other substance had a pH value of about 7 on the 0–14 paper

Answer 1

1. B. 4

   • Acid rain typically has a pH value below 5.6. A pH of 4 is indicative of acidic conditions.

2. B. 3.9

   • Apple juice is generally acidic and typically has a pH around 3 to 4, with 3.9 being a reasonable estimate.

3. D. when one substance had a pH value of about 5 and the other substance had a pH value of about 7 on the 0–14 paper

   • A follow-up test using 4.5–7.5 paper would be helpful to get a more precise measurement of substances that are closer to neutral (around 6 or 7). The pH values of 5 and 7 are within the range of that paper, making it suitable for further analysis.