1. TEXAS EDUCATION AGENCY POINT OF VIEW
IONS IN SOLUTION
TEXAS EDUCATION AGENCY POINT OF VIEW

2. DISSOLVED IONS
Substances that can conduct an electric current when they are dissolved in water are called electrolytes. Sodium chloride (NaCl) is an electrolyte because it separates into sodium ions (Na+) and chloride ions (Cl-) in solution.

3. ION CONCENTRATION
The concentration of ions in a water solution determines how much electric current the solution can conduct. Usually, the higher the concentration of ions, the more current the solution can carry.

4. Doesn’t pH have something to do with the concentration of ions?
Yes! Specifically, pH is a measure of the concentration of hydrogen ions in a solution. The pH scale goes from 0 to 14.

5. A solution with a low pH is acidic, which means that it has a high concentration of hydrogen ions (H+).

6. A solution with a high pH is basic, which means that it has a low concentration of hydrogen ions and a high concentration of hydroxide ions (OH-).

7. A solution with a pH of 7 is said to be neutral; it is neither acidic nor basic. Pure water has a pH of 7.

8. H+ + OH- → H2O
Suppose you had a solution of hydrochloric acid (HCl), which is a strong acid. What would happen if you added a small amount of a solution of sodium hydroxide (NaOH), a strong base? The hydroxide ions (OH-) from the base would react with some of the hydrogen ions (H+) from the acid to form water.

9. The overall concentration of hydrogen ions would decrease as a result of this reaction. The solution would become less acidic, and the pH would increase.

10. pH Scale 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Water Stomach Acid
Orange Juice
Ammonia
Bleach 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Strong Acid
Weak Acid
Weak Base
Strong Base
Neutral