[pinkturtle]

hi iam carrying out a titration between HCl and Na2CO3
so have decided to use methyl orange
i have searched the web and can only find really complex explainations about how methyl orange works , can anyone sum it up in a few sentences or point me in the right direction as far as web sites go

[Alberto_Kravina]

hi iam carrying out a titration between HCl and Na2CO3
so have decided to use methyl orange

What should I say-maybe it is a bit difficult to know when it's color changes- it should change from orange to pink-red (my lab teacher calls it "salmon color" ), but with a bit of practice you can easily catch the endpoint.... It isn't much, hope that this helps

[Albert]

Generally speaking, these substances are organic compounds (weak acids or bases), with high MW, that, according to the pH, are dissociated or undissociated.

The two forms have different colours because of interactions with H+ and/or -OH, such as, above all, those which produce conjugated double bonds in presence of a chromophore.