Question

1. Describe the observed effect of a strong acid and a strong base on deionized water. Your answer should be approximately one paragraph in length, including a description of the general rate and extent of change in pH under each condition. You must include your data (numbers! In this case, your pH readings) in your description.

2..Describe the difference between the effect of the acid and base on the buffers. Your answer should be approximately one paragraph in length, including a description of the general rate and extent of change in pH under each condition for your buffered solution. In your answer, you need to compare and contrast the general rates and extents of change in the pH of water and your buffered solution. You must also include your data (pH readings) in your description.

Answer 1

1) If we add a strong acid or strong base to water, the pH will change largely. For example, adding a strong acid like HCl to water results in  HCl + H2O → H3O+ + Cl-. The proton (H+) from the acid binds to neutral water molecules to form H3O+ and leads to raising the concentration of H+. The resulting large concentration of (H+) makes the solution more acidic and leads to a dramatic drop in the pH.

In case of strong bases like solid NaOH while added to water, the ions float apart leading to extra OH- ions in the water: NaOH → OH- + Na+. This results in a large concentration of OH- makes the solution more basic and leads to a dramatic increase in the pH.