Acids are characterized by their sour taste, ability to turn blue litmus paper red, and the production of hydrogen ions (H+) when dissolved in water. They typically have a pH value below 7.0. Choices B, C, and D describe properties not associated with acids, such as soapy feel, sweet taste, changing litmus colors other than to red, and yielding ions other than hydrogen ions.

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An Acid Is

Question 64

Multiple Choice

An acid is:

A) a bitter tasting chemical compound that has a pH value below 7.0, changes blue litmus to red, yields hydrogen ions in water.
B) a bitter tasting chemical compound that has a soapy feel and a pH value above 7.0, changes red litmus blue and yields hydroxyl ions.
C) a bitter tasting chemical compound that has a soapy feel and a pH value between 0 and 14, changes green litmus blue and yields hydroxyl and hydrogen ions.
D) a sweet tasting chemical solution that has a fluctuating pH value, changes orange litmus green, yields sodium ions above the 50 percentile range.

Correct Answer: