Which is not true about pH?
a. pH is representative of the concentration of hydrogen ions
b. pH can indicate the acidity or alkalinity of a substance
c. if the pH of a solution changes from 7 to 6, this indicates a 10 fold increase hydrogen
d. pH 7 is the midpoint of the scale and indicates equal amounts of hydrogen and hydroxide
e. a solution with a pH of 9 is acidic

e. a solution with a pH of 9 is acidic

Explanation:

The pH scale shows the degree of acidity or alkalinity of a substance. The scale is graduated from 0-14. pH of 0-6.9 shows acidity, 7 is the midpoint of the scale and indicates neutrality. 8-14 shows alkalinity. An increase or decrease of pH by one digit indicates a ten fold increase or decrease in hydrogen ion concentration. From the foregoing, a pH of 9 can never indicate acidity.

the answer is 0.42 is that is an option. this question provides no info

the correct answer would be b) volume versus temperature, because they are also directly proportional.