[Jules18]

What's your favourite way to calculate the equivalence point of two solutions?

I wasn't taught this way, but is it basically the same thing as the average of the pH's of both solutions?

[Borek]

Huh?

Please elaborate, question is ambiguous and/or doesn't make much sense.


Do you mean titration?

http://www.titrations.info/titration-equivalence-point-calculation

[Jules18]

Okay sry no problem.

the question I was asked was: "Find the equivalence point for the titration: 0.10M HCl and 0.10M NH₃."

So yes it's a titration. ... Is there another situation that involves an equivalence point?

[savy2020]

So yes it's a titration. ... Is there another situation that involves an equivalence point?

No, equivalence point is defined for a chemical titration. But there are different types of titrations.

Find the equivalence point for the titration: 0.10M HCl and 0.10M NH3

What do you mean by finding equivalence point?(since equivalence point is basically the situation when the titrant is exactly equivalent to solution taken)
Do you mean to calculate pH at the equivalent point?
Then write down what products you have at the equivalence point and then find the pH.

 

[Grundalizer]

Yeah I think you are missing something from the question, like perhaps the volume you have of each?  HCl and NH3 react in a 1:1 molar ratio, but as the previous poster said, the equivalence point is the point when all the HCl and NH3 have reacted and all the reactants are used up.  The end point is another term often associated with titrations, which is when a sudden change in color/pH tells the chemist that something has happened in the reaction (the end point and equivalence point should be theoretically the same), but as a chemist you don't have control over the movement of single atoms with simple glassware.  So your goal in a titration is to use the most accurate glassware you can, to get as close to the equivalence point as possible to calculate the unknown in your solution, using some kind of indicator to know when you are at that point.  Sorry, can't really add anything else with the info we have.   

[Jules18]

Yeah I think you are missing something from the question, like perhaps the volume you have of each?  HCl and NH3 react in a 1:1 molar ratio, but as the previous poster said, the equivalence point is the point when all the HCl and NH3 have reacted and all the reactants are used up.  The end point is another term often associated with titrations, which is when a sudden change in color/pH tells the chemist that something has happened in the reaction (the end point and equivalence point should be theoretically the same), but as a chemist you don't have control over the movement of single atoms with simple glassware.  So your goal in a titration is to use the most accurate glassware you can, to get as close to the equivalence point as possible to calculate the unknown in your solution, using some kind of indicator to know when you are at that point.  Sorry, can't really add anything else with the info we have.

Mmm ... considering that the equivalence point is the point at which the acid and base have completely neutralized eachother, I shouldn't need the volumes.  I just assume the volume ratios work out so that they react completely. 

I'm pretty sure if you average the pH's of both the solutions, you'll get the pH of the equivalence point. 

[savy2020]

I'm pretty sure if you average the pH's of both the solutions, you'll get the pH of the equivalence point. 

What's the basis for your statement?

This is how I'd do.
At equivlence point 0.05M NH₄Cl is formed. It is a salt of weak base and strong acid. So it undergoes cationic hydrolysis which gives a acidic solution. I'd find the pH using the equation
pH= 1/2(pK_w - pK_b - logC)
where C is concentration of salt

[Borek]

I'm pretty sure if you average the pH's of both the solutions, you'll get the pH of the equivalence point. 

So you are pretty wrong.

0.1M HCl - pH 1.00
0.1M NH₃ - pH 11.12
equivalence point - pH 5.12

Instead of guessing check the link I listed.

Besides, equivalence point is not property of "solutions" as you have asked in your first post. There will be no equivalence point if you mix solution of HCl and solution of H₂SO₄.