Which of the following is correct?
A)A substance with pH of 3 is 10 times as Acidic as a substance with a pH of 4.
B)A substance with a pH 3 is twice as acidic as a substance with a pH of 4.
To determine which statement is correct, we need to understand the concept of pH and its scale. The pH scale measures the acidity or basicity (alkalinity) of a substance, ranging from 0 to 14.
The pH scale is logarithmic, meaning that each whole number increase or decrease represents a tenfold difference in acidity. For example, a substance with a pH of 2 is ten times more acidic than a substance with a pH of 3.
Now let's evaluate the statements:
A) "A substance with a pH of 3 is 10 times as acidic as a substance with a pH of 4."
This statement is correct. According to the logarithmic nature of the pH scale, each decrease of one unit represents a tenfold increase in acidity. Therefore, a substance with a pH of 3 is indeed 10 times more acidic than a substance with a pH of 4.
B) "A substance with a pH of 3 is twice as acidic as a substance with a pH of 4."
This statement is incorrect. As mentioned earlier, each whole number difference on the pH scale represents a tenfold difference in acidity. Therefore, a substance with a pH of 3 is actually ten times more acidic, not just twice as acidic, compared to a substance with a pH of 4.
To summarize, statement A is correct: "A substance with a pH of 3 is 10 times as acidic as a substance with a pH of 4."