Titration Questions Help (1 Viewer)

[dhampoet]

Could you help me with these questions?

Base is the known concentration

1. Is is error or correct?Why the pipette is rinsed with the base?
2. Is is error or correct?Wht the conical flask is rinsed with the base?
3. We tritrate HCL with NaCO3. Is Methyl orange indicator the correct indicator to use?
4. Is six drops of indicator added to the flask corret or error?why?
5. Is it error or correct?Why the burette is rinsed with distilled water?
6. Is it error or correct?Why the sides of the flash are washed down with distilled water?

7. Compare and evalutae the use of a digital (computer based) means of determining the acid concentration with the method used. Comment on the validity and the accuracy of both methods.
What is digital means?I couldn't find it on the textbooks

8. Asses the reliability of the results

 

[xiao1985]

yes
no
yes
no - indicators are acidic in nature, you only need 2 max
no - soln which you will burette will hold
flash?!?!
digital = pH probe instead of indicator

 

[kathrynso]

I think no. 6 was meant to be *flask. and yes you rinse the flask with distilled water as it wont change any results you need

 

[karnage]

1. The pipette is rinsed with the acid to remove any foriegn matter inside it. Basically to clean it out.
2. Conical flask is rinsed out with distilled water, reasoning as said above.
3. Not sure, we just use universal indicator.
4. Well i've been told to put in 3 drops so yea...
5. Burette is rinsed (not literally rinsing, just putting some in and cleaning the insides) with the base.
6. Just if theres some base or acid stuck on the sides of the flask during the titration process.

 

[xiao1985]

pretty much correct.

base or acid goes into the burette is really personal preference now days... in the old days, base ALWAYS goes in the conical flask... it is my personal belief that it should be done that way still, as base is likely to screw up the burette

NEVER use universal indicator as an indicator for titration. the colour change is way to vague to be accurate.

 

[karnage]

NEVER use universal indicator as an indicator for titration. the colour change is way to vague to be accurate.

Yeah i figured something was wrong. Im not sure what its called but i'll definitely find out what we use.

Anyone in the NSW titration comp?

 

[MollyGirl36]

Basically, you rinse the equipment with wateva you r going to be putting in it. If you are going to put base in the burette, rinse the burette with the base. It doesn't matter what you put in the burette or the pipette as long as you know the accurate amount of base used to reach the endpoint