Because it turns red at pH 9.7 ish, and adding one drop of NaOH to the acid just before neutralisation takes the pH to pH 10
but for methyl orange for eg. the end point is always orange, it doesnt take the color of the excess and change to yellow.. why does phenolphthalein take the color of the excess
but for methyl orange for eg. the end point is always orange, it doesnt take the color of the excess and change to yellow.. why does phenolphthalein take the color of the excess
We added an alkaline (NaOH) to an acid solution, the final pH would be higher than before, phenolphthalein is red/pink in alkaline conditions and colourless in acid conditions, therefore since the pH is higher than before, the colour change would be from colourless to pink/red
same goes for methyl orange, it is orange/yellow in alkaline conditions and red in acidic conditions
We added an alkaline (NaOH) to an acid solution, the final pH would be higher than before, phenolphthalein is red/pink in alkaline conditions and colourless in acid conditions, therefore since the pH is higher than before, the colour change would be from colourless to pink/red
same goes for methyl orange, it is orange/yellow in alkaline conditions and red in acidic conditions
so is the end point the neutral color or the excess of the reactant added(the titre)?
then why is methyl orange always orange at the end point of the titration not red
No the colour change depend on the titre, on the reactant in the flask and on the pH change!!
For methyl orange, it turns orange when an alkaline solution is added (titre), the end point is when the colour change occurs from red to orange, it occurs because if there was an acid the the flask and an alkaline was added from beurette then at the end point, all of the acid would have been neutralised and excess alkali would be found in the flask which causes the colour change to occur
No the colour change depend on the titre, on the reactant in the flask and on the pH change!!
For methyl orange, it turns orange when an alkaline solution is added (titre), the end point is when the colour change occurs from red to orange, it occurs because if there was an acid the the flask and an alkaline was added from beurette then at the end point, all of the acid would have been neutralised and excess alkali would be found in the flask which causes the colour change to occur
sooo now the end point is yellow?? not orange.. bcz there's excess alkali