Buffers and Titrations

Buffer Questions & Answers:

Why do we care about buffers?

• It will keep pH constant upon adding acid or base

What do we need in a buffer?

•  a weak acid (𝐻𝐴) and its conjugate base (𝐴−)

  • if we add a base, it will react with the acid

  • if we add an acid, it will react with the base

You might ask, “can any buffer work?”

• the desired pH is +/-1 from the buffer 𝑝𝐾𝑎

When is a buffer no longer a buffer?

• When you use up one entire species from weak acid/conjugate base pair

What unit should I work in when I am using buffers?

• MOLES

Things to consider when making a buffer:

• pH +/- 1 from 𝑝𝐾𝑎

• What materials you have available (you can make a buffer multiple ways)

  • option 1: 2 solids ([𝐻𝐴] and [𝐴−])

  • option 2: 1 solid and 1 solution ([𝐻𝐴] solid & [𝐴−] solution)

  • option 3: 1 solid and 1 solution ([𝐻𝐴] solution & [𝐴−] solid)

• use Henderson-Hasselbach Equation

Acids, Bases, and Buffers (11:52)