Editing Effects Of Adding A Strong Acid (Or Base) To A Solution

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So you add a strong acid or a strong base to a solution, 
 
What happens?

Answer

For any solution, the added strong acid (therefore H+) or the strong base (therefore OH1-) will be consumed by the available acid/base until there is either no more added strong acid/strong base or the acid/base in the solution is gone. This is determined by STOICHIOMETRY calculation (net ionic equation is 1 H+ + 1 OH1- --> 1 H2O). Then you re-evaulate the type of bucket (all the resulting species and their concentration in the bucket).

So what does this mean for Calculating method for Equilibrium systems?

The stoichiometry calculation and resulting concentration changes for all the species in the bucket will come before you determine the major species in the bucket (STEP 1) and the resulting analysis of which reaction is "running the show" in the bucket.

What are the most common calculations using this concept (adding strong acid/base to a solution)?

1) A buffer (either acidic or basic) and its buffering capacity. (AP Book: Section 15.3) 
*[http://www.tmcleod.org/AP/APAcidBaseII/APNotesStrongAddtoBuffer.pdf AP Notes on Calculating pH when Adding Strong Base to a Acid Buffer] 
 
2) Titrations and Titration Curves ("titrated by" means you are adding that solution one drop at a time to the total volume of other solution) ( AP Book: Section 15.4)

The following are major points on the Titration Curve and notes on how to calculate the pH of the solution. 
*A general note, even if the question is in a series of problems, you still assume that each question has its own bucket and you start from "scratch" and not from the point of the previous problem (i.e. question is what is pH of each solution if you add 5.0ml, 15.0ml and 25.0ml of strong base to a 500ml 1.0M weak acid solution. Treat each as separate problems, so it is as if you have 3 separate problems).

*Strong Acid titrated by a Strong Base ( 50.0ml of 0.200M <nowiki>HNO</nowiki>3 titrated by 0.100M <nowiki>NaOH</nowiki>) 
**Original bucket
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesSA0mlSB.pdf 0.0ml NaOH added so simple Strong Acid Bucket]
**No buffering zone so no Half way point
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesSA10mlSB.pdf 10.0ml NaOH added]
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesSA50mlSB.pdf 50.0ml NaOH added]
**Equivalence point
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesSA100mlSB.pdf 100.ml NaOH added, Equivalence Point]
**Exceeded Equivalence point
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesSA150mlSB.pdf 150.ml NaOH added]
 
*Weak Acid titrated by a Strong Base ( 50.0ml of 0.100M HC2H3O2, HAc, titrated by 0.100M <nowiki>NaOH</nowiki>) 
**Original bucket
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesWA0mlSB.pdf 0ml NaOH added, simply Weak Acid Bucket]
**(In Buffering zone)
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesWA10mlSB.pdf 10ml NaOH added, Buffering Zone]
**Half-way Point (part of Buffering Zone)
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesWA25mlSB.pdf 25ml NaOH added, Halfway point]
**Equivalence point
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesWA50mlSB.pdf 50ml NaOH added, Equivalence Point]
**Exceeded Equivalence point
***[http://www.tmcleod.org/AP/APAcidBaseII/APNotesWA75mlSB.pdf 75ml NaOH added]
 
 
*Strong Base titrated by a Strong Acid
**Original bucket
**No buffering zone so no Half way point
**Equivalence point
**Exceeded Equivalence point
*Weak Base titrated by a Strong Acid
**Original bucket
**Half way point (since there is Buffering zone)
**Equivalence point
**Exceeded Equivalence point
*Note: At this level of chemistry/math, there is no "titrated by" weak acid or weak base.

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