Question

When acids are added to a solution, the pH should ________?

1) decrease
2) increase
3) stay the same
4) cannot tell without testing

Answer 1

When acids are added to a solution, the pH should decrease. Acids increase the hydronium ion concentration, leading to a lower pH value. For instance, as you go from neutral water to acid concentrations of 0.01M and then 0.10M, the pH decreases successively from 7 to 2 to 1.

Step-by-step explanation:

When acids are added to a solution, the pH should decrease. Acids increase the concentration of hydronium ions in the solution, which results in a lower pH number. The pH measures the relative acidity or concentration of protons (hydrogen ions) in a solution. An acidic solution has a pH value below 7. The more acidic a solution is, the lower the pH values will be. For instance, adding 0.01M and then 0.10M of an acid to neutral water will result in the pH decreasing from 7 to 2 and finally to 1, respectively.

To answer the question about identifying substances as acidic, basic, or neutral, you would look at their pH values:

• Human blood, pH = 7.4, is slightly basic as it's above 7.
• Household ammonia, pH = 11.0, is basic.
• Cherries, pH = 3.6, are acidic.