Question

check all of the following that are characteristics of buffers.
check all that apply
□ can pick up excess h⁺
□ can release h⁺ when h⁺ is lacking
□ helps maintain ph
□ causes acidosis

Explanation:

• A buffer is a solution that resists changes in pH. It contains a weak acid and its conjugate base (or a weak base and its conjugate acid).
• When there is excess $\ce{H+}$ (acidic conditions), the conjugate base in the buffer can react with the excess $\ce{H+}$ (pick up excess $\ce{H+}$) to form the weak acid.
• When $\ce{H+}$ is lacking (basic conditions), the weak acid in the buffer can dissociate to release $\ce{H+}$.
• By doing these two things (picking up excess $\ce{H+}$ and releasing $\ce{H+}$ when needed), buffers help maintain a relatively stable pH.
• Acidosis is a condition where the pH of the body (or a solution) becomes too acidic, and buffers actually help prevent acidosis (and alkalosis) by maintaining pH, so "Causes acidosis" is incorrect.

Answer:

• $\boldsymbol{\square}$ Can pick up excess $\ce{H+}$ (should be checked)
• $\boldsymbol{\square}$ Can release $\ce{H+}$ when $\ce{H+}$ is lacking (should be checked)
• $\boldsymbol{\square}$ Helps maintain pH (should be checked)
• $\boldsymbol{\square}$ Causes acidosis (should not be checked)

So the correct options to check are "Can pick up excess $\ce{H+}$", "Can release $\ce{H+}$ when $\ce{H+}$ is lacking", and "Helps maintain pH".