It shows how a buffer equilibrium shifts to minimize the change in hydronium ion concentration, and therefore pH, when a base is added.

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0:02in
0:05them will use equilibrium concept to explain how a buffer solution
0:11minimizes change in pH when a small amount it pays
0:15sad will start out by considering a buffer solution
0:19in which the concentration of acetic acid and the concentration of the
0:23acetate
0:24I N are both one molar here's the equilibrium equation describing this
0:29buffer
0:30because this is in a clear solution
0:36any changes in the amount of water in this equilibrium
0:39are insignificant
0:41will discolor the water blue and we won't be concerned with it
0:46concentration of hydrazone a.m. in this equilibrium
0:49is much lower than the one molar concentrations a scenic acid
0:53and acetate
0:56now will construct grafts showing how the concentrations above the three
1:00species in the equilibrium or very
1:02when we add a base to this but fair and it really just
1:07this sample shows that the yaxis on these graphs
1:11is actually much longer then portrayed in the diagram
1:16the one molar concentrations %uh vissi dick acid acetate I am
1:20are considerably higher than that the hydrazone mine
1:24first will consider the concentrations %uh the three species
1:28before we at the base
1:31concentrations above all three species remain constant
1:36at this point we added babies like any wage to this buffer
1:40baseball react with the 830 bus and neutralize it
1:43as shown in this net ionic equation
1:48in this new july's asian reaction I don't you miss consumed
1:51so this will decrease the concentration at age 30 plus
1:56so we had the base and the concentration at age 30 plus
1:59quickly decreases
2:01adding a base had no immediate effect on the concentration embassy
2:05kassin or on the concentration of the acetate
2:09I N
2:10but the sudden decrease in the hydrazone mine concentration that took place when
2:15the base was added
2:16causes stress on the equilibrium system
2:19because hydro name is a product whose concentration has been decreased
2:24the equilibrium will shift to the right in order to compensate
2:30as the shift to the right occurs the concentration of hydrazone M
2:34gradually increases as it partially compensates for this sudden drop
2:39the acetate diane is also a product there was this shift to the right occurs
2:44its concentration will gradually increase like the hydrazone mines
2:48concentration did
2:50SEP Cassidy is a reactant so as the shift to the rakers
2:55its concentration will gradually decrease
3:01when the shift to the right is complete a new equilibrium is established
3:05so as time continues the concentrations above all three species
3:09remain constant and the lines in the graph or horizontal
3:14in the overall process the concentration up a CD Kasson
3:18showed a net decrease
3:20and the concentration of the acetate I N
3:23showed a net increase
3:25the concentration of hydrazone a.m. dropped rapidly when the base was added
3:31as the equilibrium shifted to the right and by freeing took place
3:34the hydrazone mine concentration
3:37gradually increased in order to partially compensate for the drop
3:42so in the overall process the hydrazone mine concentration showed a very small
3:46net decrease
3:49now will consider the changes in pH as the basis that it
3:53and the system adjusts
3:55remember pH is the negative log up the hydrazone mine concentration
4:00the negative sign means as the concentration at age 30 plus goes down
4:05the pH goes up
4:08so when the base was first added as the hydrazone mine concentration goes down
4:13the pH goes up
4:16as the shift to the right occurs and the concentration of hydrazone and gradually
4:20increases
4:22the pH gradually decreases
4:25so in the overall process as the hydrazone mine concentration
4:29shows a very small net decrease
4:33the pH shows a very small net increase
4:37if there were no buffer solution president and we added a base to water
4:41DPH would quickly right but there's nothing to buffer it is rise
4:47so the pH will remain at this level
4:50did and show a large net increase
4:54in the overall process instead a small net increase experienced by the buffer
4:59solution
5:00the buffer has accomplished its purpose it is minimized the change in pH
5:06resulting from the addition obeys ok
5:12are