Final answer:
The pH of a diabetic's blood is lower than that of normal blood, which means it is more acidic. This is because the lower the pH, the higher the concentration of hydronium ions and the more acidic the substance. Therefore the correct option is B.
Step-by-step explanation:
The pH scale measures how acidic or basic a substance is. It ranges from 0 to 14. A pH of 7 is neutral, anything below 7 is acidic, and anything above 7 is basic. The logarithmic nature of the pH scale means that each unit represents a ten-fold difference in acidity of the solution. Therefore, a pH of 6 is ten times more acidic than a pH of 7.
Given this, we can deduce that Option B: 'The diabetic's blood is more acidic than normal blood' is correct. This is because, at a pH of 6.4, the diabetic's blood has a higher concentration of hydronium ions ([H3O+]) compared to the normal blood at a pH of 7.4, making it more acidic.
Learn more about pH scale