The indicator used in titrating a weak acid (e.g.,oxalic acid) with a strong base (e.g.,caustic soda) solution is

Which indicator is used for the titration of $CH_3COOH$ and $NaOH$?

Given below are two statements :-
Statement $I$ :- Methyl orange is a weak acid.
Statement $II$ :- The benzenoid form of methyl orange is more intense/deeply coloured than the quinonoid form.
In the light of the above statements,choose the most appropriate answer from the options given below :-

The pink colour of phenolphthalein in an alkaline medium is due to -

For an acid indicator with $K_{in} = 1.0 \times 10^{-5}$, the color change occurs when the concentration of the indicator is $1 \times 10^{-3} \ M$. Find the $pH$ at which the color change occurs.

Methyl orange is an indicator in acid-alkali titration. It gives