A has more hydrogen ions (as substance A is acid) and substance B is basic.....

Introduction:
pH is a measure of the concentration of hydrogen ions (H+) in a solution. The pH scale ranges from 0 to 14, with a pH of 7 being neutral. Solutions with a pH less than 7 are acidic, while solutions with a pH greater than 7 are basic or alkaline. In this case, we have two solutions, A and B, with pH values of 6 and 8, respectively.

Comparison of Hydrogen Ion Concentration:
The pH scale is logarithmic, meaning that each whole number change in pH represents a tenfold change in hydrogen ion concentration. In other words, a solution with a pH of 6 has ten times more hydrogen ions than a solution with a pH of 7, and a solution with a pH of 8 has ten times fewer hydrogen ions than a solution with a pH of 7.

Considering this, we can determine which solution has a higher hydrogen ion concentration:

- Solution A (pH 6) is more acidic than Solution B (pH 8).
- Solution A has a higher hydrogen ion concentration than Solution B.

Explanation:
1. Solution A (pH 6):
- Solution A has a pH of 6, which is less than 7.
- This indicates that Solution A is acidic.
- The lower pH value of Solution A means it has a higher concentration of hydrogen ions compared to Solution B.
- The higher concentration of hydrogen ions in Solution A contributes to its acidic properties.

2. Solution B (pH 8):
- Solution B has a pH of 8, which is greater than 7.
- This indicates that Solution B is basic or alkaline.
- The higher pH value of Solution B means it has a lower concentration of hydrogen ions compared to Solution A.
- The lower concentration of hydrogen ions in Solution B contributes to its basic properties.

Summary:
- Solution A (pH 6) has a higher concentration of hydrogen ions compared to Solution B (pH 8).
- Solution A is acidic, while Solution B is basic.
- The pH scale is logarithmic, and each whole number change in pH represents a tenfold change in hydrogen ion concentration.
- Understanding the pH scale helps us determine the relative acidity or basicity of different solutions.