Strong acids have a pH of ______ and below.

Strong acids have a pH of ______ and below.

• A. 0
• B. 1
• C. 2
• D. 3

Answer: (C)

Strong acids completely dissociate in water, so their hydrogen ion concentration becomes relatively high. Since pH is the negative logarithm of [H+], higher [H+] yields a lower pH. In typical educational examples, common strong-acid solutions give pH values around 0 to 2 (for example, 1 M HCl is about pH 0, 0.01 M is pH 2). Therefore, a general statement used in many contexts is that strong acids have a pH of 2 or below. While extremely concentrated acids can push pH below 0 and very dilute ones can approach higher pH, the standard teaching bound that fits the usual range is 2 and below.

Strong acids completely dissociate in water, so their hydrogen ion concentration becomes relatively high. Since pH is the negative logarithm of [H+], higher [H+] yields a lower pH. In typical educational examples, common strong-acid solutions give pH values around 0 to 2 (for example, 1 M HCl is about pH 0, 0.01 M is pH 2). Therefore, a general statement used in many contexts is that strong acids have a pH of 2 or below. While extremely concentrated acids can push pH below 0 and very dilute ones can approach higher pH, the standard teaching bound that fits the usual range is 2 and below.