The $pH$ range of methyl orange as an indicator is in between:

For an acid-base indicator,the dissociation constant $K_a = 1.0 \times 10^{-5}$. The indicator is red in acidic form and blue in basic form. What is the $pH$ range required for the color change from $80\%$ red to $80\%$ blue?

$A$ compound '$X$' is a weak acid and it exhibits colour change at $pH$ close to the equivalence point during neutralization of $NaOH$ with $CH_3COOH$. Compound '$X$' exists in ionized form in basic medium. The compound '$X$' is.

The titration curve of a weak acid vs. a strong base with phenolphthalein as an indicator is shown below. The $K_{In} = 4 \times 10^{-10}$. Given: $\log 2 = 0.3$. The number of the following statements which is/are correct about phenolphthalein is $.....$.
$A$. It can be used as an indicator for the titration of a weak acid with a weak base.
$B$. It begins to change colour at $pH = 8.4$.
$C$. It is a weak organic base.
$D$. It is colourless in an acidic medium.

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.

At what $pH$ will an indicator with $K_b = 1 \times 10^{-11}$ show a color change in a $1 \times 10^{-4} \ M$ solution?