The indicator HIn has a dissociation constant of 1*10^-4 M.

HIn<===> H30^+ + In^-
Yellow Red

When the pH value of the solution is 7,
1)the indicator shows the colour red

2)at this time most of the indicator has been dissociated

Which statements are true?

1)I took this as false cause the pH range of the indicator is given by pkIn+/-1,so as it indicates the colour red when H3O^+ is released.
So here it should indicate colour yellow.am I correct?

And what about the 2nd one?

As I see it you have this:

KIn = 1E-4 = (H^+)(In^-)/(HIn) or
1E-4/(H^+) = (In^-)/(HIn) = 1E3 which tells me that mos of the indicator is in the form In^-. So 2 should be true? What does that tell you about 1?

So the solution is acidic? So it should indicate the acidic colour? Am I correct?

Couldn't change the name.My sister was also using the PC to access this site

If most of the indicator is in the In^- form, is that the acid or the base form?

A H atom is released from HIn so it is acidic?

The ratio of In^-/HIn is what counts. The pH tells you what that ratio is, as I showed in the answer to part 2. If most of the indicator is in the acid form it will be yellow; if most in the base form it will be red. The fact that the ionization of HIn produces H^+ doesn't answer the question. The pH of the solution tells the HIn ==> H^+ + In^- equilibrium which way to shift; i.e., to the left as H^+ is increased and to the right as H^+ is decreased.

The statement "The indicator shows the color red when the pH value of the solution is 7" is actually correct. The dissociation constant, also known as pKa, is an indicator of the pH range in which the indicator changes color. In general, when the pH of a solution is higher than the pKa, the indicator will be in its basic form (HIn) and show one color, and when the pH is lower than the pKa, the indicator will be in its acidic form (In-) and show a different color.

In this case, the pKa of HIn is given as 1*10^-4 M. Since water has a pH of 7, which is greater than the pKa, the indicator will exist mostly in its basic form (HIn) and show the color red.

Therefore, statement 1 is correct.

For statement 2, when the pH of the solution is 7, it means that the concentration of H3O+ (hydronium ion) is equal to the concentration of OH- (hydroxide ion), which is 1 x 10^-7 M. Given that the dissociation constant of the indicator is 1 x 10^-4 M, we can compare the concentrations to determine the extent of dissociation.

Since the concentration of H3O+ ions is much lower than the dissociation constant, it means that most of the indicator molecules are still in their non-dissociated form (HIn), rather than being dissociated into H3O+ and In-. Therefore, statement 2 is false. Most of the indicator has not been dissociated in this case.

So, to summarize:

1) True. The indicator shows the color red when the pH value of the solution is 7.

2) False. Most of the indicator has not been dissociated when the pH value is 7.