in a lab we had to do we had to explore the effect of a buffer.
we had a test tube of milk and a test tube of water.
we then added a drop of vinegar to each.. one frop at a time.. to see if the pH would change
we found out that the pH of water changed first... but i dont know why it did or what it had to do with the buffer.
2007-12-15 08:43:33 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Biology
The acid from the vinegar reacted with solutes in the milk. As long as the solutes remained to react with the acid and neutralize it the pH was not free to change. Once the solute had been consumed by the reaction the milk pH changed just as the water, that lacked a reactive reagent, did.
Milk contains casein, calcium phosphate Ca3(PO4)2, and citrate that can act to buffer acids. The acid reacts with the weak aqueous base.
Aqueous solutions contain -OH3+ & -OH- so small additions of of acid or base react rather than change the pH.
Acid added consumes the hydroxide ions.
2007-12-15 10:14:46 · answer #1 · answered by gardengallivant 7 · 0⤊ 0⤋
A buffer prevents pH from changing as quickly. The idea is that the milk contains a buffer naturally, but water does not.
2007-12-15 17:12:55 · answer #2 · answered by ecolink 7 · 0⤊ 0⤋
The buffer was the controlled variable in order for the reaction to occur in.
2007-12-15 16:46:55 · answer #3 · answered by Hi! 3 · 0⤊ 0⤋