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Chemistry mole calculation problem (help me)

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Saladin:
The answer they wanted here was not a concentration value, they wanted to know how many hydrogen atoms are in a molecule of Citric acid.

nid404:
Citric acid conc= 19.2/192 mol/dm3 = 0.1 mol/dm3
conc=mol/dm3
No of moles=0.005 (50/1000dm3 X 0.1)

Mr of NaOH= 40
NaOH conc= 12/ 40 = 0.3 mol/dm3

Vol of NaOH that reacted= 50cm3
Moles of NaOH that reacted= 0.0015

In fact theres no need to find the moles. Ratio of conc gives the ratio of moles since volume is same.

Ratio of citric acid to NaOH is 1:3

HxA+ 3NaOH --> Na3A + 3H2O

x=3

nid404:
Hope this is clear.

Saladin:

--- Quote from: ~Ahana~ on August 20, 2010, 07:13:33 pm ---Citric acid conc= 19.2/192 mol/dm3 = 0.1 mol/dm3
conc=mol/dm3
No of moles=0.005 (50/1000dm3 X 0.1)

Mr of NaOH= 40
NaOH conc= 12/ 40 = 0.3 mol/dm3

Vol of NaOH that reacted= 50cm3
Moles of NaOH that reacted= 0.0015

In fact theres no need to find the moles. Ratio of conc gives the ratio of moles since volume is same.

Ratio of citric acid to NaOH is 1:3

HxA+ 3NaOH --> Na3A + 3H2O

x=3




--- End quote ---

Ahh man, I messed up! :(

Sorry for the inconvenience. I just messed up for some reason. It was a really simple sum :(

xim7007:
Thanks guys for ur kind help.

I was trying to do it this way. I found out the amount of citric acid and amount of NaOH in moles. I got 0.005 moles of citric acid reacts with 0.015 moles of NaOH, so 1 mole of citric acid reacts with 3 moles of NaOH. But I don't how to carry out further calculation to find the value of X. can u explain how to calculate the value of X using this method?  :)

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