L3.4: Buffers

• Buffers

  ● A solution whose pH changes very little when acid or base is added.

  ● Most buffer are solutions composed of roughly equal amounts of:

  ○ Weak acid

  ○ Salt of its conjugate base

  ● Buffer resists change in pH because:

  ○ Added base, OH-, reacts with weak acid.

  ○ Added acid, H3O+, reacts with conjugate base.
• Buffers

  ● If acid is added to a buffer, then excess acid reacts with the conjugate base, neutralizing one another, hence not affecting overall pH as much.

  ● If base is added to a buffer, then excess base reacts with the conjugate acid, neutralizing one another, hence not affecting overall pH as much.
• Medical Applications

  ● Normal blood pH is between 7.35 to 7.45.

  ● The principal buffer in blood is carbonic acid / bicarbonate (H2CO3 / HCO3-).

  ● Respiratory alkalosis (too basic) is caused by hyperventilating; meaning very little CO2 is produced in our body.