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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: psych93 on March 06, 2011, 07:24:43 pm

Title: Does temperature affect titrations?
Post by: psych93 on March 06, 2011, 07:24:43 pm

We did the nitrogen fertiliser back titration...
Our sodium hydroxide solution was boiled to get rid of the ammonia and then immeditely titrated with HCl. Does the tempertaure of the solution affect the titration in anyway?
oh and we also heated our BaSO4 precipitate in the gravimetric analysis prac (sulfur in fertilier) and then the solution was filtrated and the precipitate was collected.
Does this have any effect on the results?


Also with the titration graph... if you're titrating a strong base against a strong acid (base in flask, acid in burette) will the graph start at around 14 and end at around 1??? So the equivalence point should be around 7-7.5?? We used phenophalein as an indicator... and I don't think it was the most suitable choice as an indicator because it changes colour at ph8-10

Title: Re: Does temperature affect titrations?
Post by: omgwtf123 on March 06, 2011, 08:31:21 pm

Wouldn't Bromothymol blue be a more suitable indicator for use between a strong base and a strong acid?

Title: Re: Does temperature affect titrations?
Post by: Mao on March 06, 2011, 08:33:01 pm

It is possible titrations are affected by temperature. The pH range for indicators can change with temperature.

Title: Re: Does temperature affect titrations?
Post by: Mao on March 06, 2011, 08:34:59 pm

Quote from: omgwtf123 on March 06, 2011, 08:31:21 pm

Wouldn't Bromothymol blue be a more suitable indicator for use between a strong base and a strong acid?

Not necessarily, most indicators would be suitable since the change in pH is sharp.

Title: Re: Does temperature affect titrations?
Post by: omgwtf123 on March 06, 2011, 08:38:46 pm

mmm k, i see

Title: Re: Does temperature affect titrations?
Post by: burbs on March 06, 2011, 09:00:36 pm

Temperature can affect speed of reactions right? So maybe extreme temperatures could?

Title: Re: Does temperature affect titrations?
Post by: zool3 on March 08, 2011, 04:31:14 pm

heat increases the speed of the particles. they move more rapidly and react with each other a lot faster, rather than letting them react slowly or stirring