In a buffer you have two distinct chemicals there. One is HCOOH and the other is HCOONa which gives the HCOO^- ion.
If you add acid it is the base that does the work as
HCOO^- + H^+ ==> HCOOH
If you add base(OH-) is is the acid that does the work.
HCOOH + OH^- ==> H2O + HCOO^-
Sodium methanoate, NaHCOO, and methanoic acid, HCOOH, can be used to make a buffer solution. Explain how this combination resists changes in pH when small amounts of acid or base are added.
Buffers kind of confuse me and I'm not sure how to start this. Can someone help me to come up with the chemical equation for this? I think I'll know how to explain it from there.
Would it be like NaHCOO + HCOOH -> ...? That doesn't seem right though.
2 answers
Oh okay so they have two distinct jobs, but they're still together in the solution? For example in a lab or something, both chemicals would be mixed inside one beaker?
Is this explanation right?:
If an acid is added, the H3O+ ions will be removed by NaHCOO, which produces HCOO- ions:
HCOO- + H3O+ -> HCOOH + H2O
It creates HCOOH, a component that is already in the solution, and water, which is a neutral substance. Thus, the pH will not change (until the buffer capacity is reached).
If a base is added, the OH- ions will be removed by HCOOH:
HCOOH+ + OH- -> HCOO- + H2O.
{same explanation as above}
Is this explanation right?:
If an acid is added, the H3O+ ions will be removed by NaHCOO, which produces HCOO- ions:
HCOO- + H3O+ -> HCOOH + H2O
It creates HCOOH, a component that is already in the solution, and water, which is a neutral substance. Thus, the pH will not change (until the buffer capacity is reached).
If a base is added, the OH- ions will be removed by HCOOH:
HCOOH+ + OH- -> HCOO- + H2O.
{same explanation as above}
1 answer