The pH scale ranges from 0 to 14. Which statement best describes this range?

The pH scale ranges from 0 to 14. Which statement best describes this range?

• A. 0 to 14
• B. 7 to 14
• C. 0 to 12
• D. 0 to 7

Answer: (A)

The pH scale is a logarithmic measure of hydrogen ion activity in water, set so that at standard room temperature neutral is 7, acids are below 7, and bases are above 7. This creates a full practical range from 0 (strongly acidic) to 14 (strongly basic). Since 0 to 14 covers the entire spectrum of common aqueous solutions, describing the range as 0 to 14 is the most complete statement. Some of the other ranges only capture part of the scale—for example, 7 to 14 covers basic to neutral, and 0 to 7 covers acidic to neutral—so they don’t describe the full range.

The pH scale is a logarithmic measure of hydrogen ion activity in water, set so that at standard room temperature neutral is 7, acids are below 7, and bases are above 7. This creates a full practical range from 0 (strongly acidic) to 14 (strongly basic). Since 0 to 14 covers the entire spectrum of common aqueous solutions, describing the range as 0 to 14 is the most complete statement. Some of the other ranges only capture part of the scale—for example, 7 to 14 covers basic to neutral, and 0 to 7 covers acidic to neutral—so they don’t describe the full range.