To determine the pH of acids, we need to understand the pH scale and how it classifies substances. The pH scale ranges from 0 to 14 and is used to measure the acidity or basicity of a solution:
- A pH value between 0 and 7 indicates an acidic solution, with lower values being more acidic.
- A pH value of exactly 7 is considered neutral, which is typically the pH of pure water.
- A pH value between 7 and 14 indicates a basic (alkaline) solution, with higher values being more basic.
- A pH value above 14 is not common in standard measurements.
Since acids are known to have a pH below 7, we can go through the options and determine the correct one:
A. between 7 and 14 - This range indicates basic (alkaline) solutions, not acidic ones.
B. equal to 7 - This indicates a neutral solution.
C. below 7 - This range indicates acidic solutions.
D. above 14 - This value is not typically observed in standard conditions and does not apply in this context.
Therefore, based on the pH scale, the correct option that describes the pH of acids is:
C. below 7
