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Help needed urgently

Did this a few weeks ago, didn't write down my method and have forgotten how to calculate it. Have got 2 answers but don't know how I reached them. I have 0.53g and 1.06g. Which one is right?


You are to find the precise concentration of a solution of hydrochloric acid. You are told that the acid has a concentration somewhere between 0.08 mol. dm-3 and 0.12 mol. dm-3 . The concentration of the acid is to be determined by titration with a solution of sodium carbonate. Using suitable calculations, suggest a suitable mass of sodium carbonate to add to water to make 100 cm3 of the standard solution. Use the information below to help you in your calculations:-

volume of volumetric flask = 100 cm3
volume of burette = 25 cm3
Volume of pipette = 10 cm3

Note that during the titration the burette should not need to be refilled.
(edited 5 years ago)
Original post by UAV
Did this a few weeks ago, didn't write down my method and have forgotten how to calculate it.

There may be learning for you in just this :smile:
Reply 2
Original post by ChemistryWebsite
There may be learning for you in just this :smile:

I'm just about getting the hang of finding mass needed to make up a solution with given concentration. I'm not so sure about this one though as there's no concentration given? Would appreciate some help
Original post by UAV
I'm just about getting the hang of finding mass needed to make up a solution with given concentration. I'm not so sure about this one though as there's no concentration given? Would appreciate some help

Step 1 is deduce the balanced equation for the reaction between hydrochloric acid and sodium carbonate.
What is their reaction ratio? (the Stoichimetry of the reaction)
Reply 4
Original post by ChemistryWebsite
Step 1 is deduce the balanced equation for the reaction between hydrochloric acid and sodium carbonate.
What is their reaction ratio? (the Stoichimetry of the reaction)


2:1 ratio

2HCl +Na2CO3 ---> 2NaCl+H2O+CO2
Original post by UAV
2:1 ratio

2HCl +Na2CO3 ---> 2NaCl+H2O+CO2

Good.
Next, what titration volume would you think is ideal? (Roughly)
Reply 6
Original post by ChemistryWebsite
Good.
Next, what titration volume would you think is ideal? (Roughly)


I have done the titration already, I used 0.53g. my average titre volume required was 10.35

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