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During neutralisation of an acid by a ba...

During neutralisation of an acid by a base, the end point refers for the completion of reaction. The detection of end point in acid -base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthlein) or a weak base (Mrthyl orange). At about `50%` ionisation which depends on the medium, the anion furnished by an indicator (acid) or cation furnished by indicator (basic) imparts its characteristic colour to solution at point. For example phenolphthalein, the dissociation is
`underset("Colourless")(H In hArr H^(+))+underset("Pink")(In^(-)), K_(H In)= ([H^(+)][In^(-)])/([H In])`
favoured in presence of alkali and pink colour of phenolphalein ion is noticed as soon as the medium changes to alkaline nature. The end point of acid-base neutralisation not necessarily coincides with equivalent point but it is closer and closer to equivalence point. Also at equivalence point of acid-base neutralisation pH is not necessarliy equal to 7.
Which among the following statements are correct ?
(1) At equivalence point of NaOH and HCI, pH = 7
(2) At equivalence point to of NaOH and `CH_(3)COOH,pH gt 7`
(3) At equivalence point of `NH_(4)OH` and `HCI, pH lt 7`
(4) an indicator shoes best results, if equivalence point is within the pH range `pK_(a)` of In `+1`
(5) At equivalence point of `NH_(4)OH` and formic acid, `pH lt 7`

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During neutralisation of an acid by a base, the end point refers for the completion of reaction. The detection of end point in acid -base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthlein) or a weak base (Mrthyl orange). At about 50% ionisation which depends on the medium, the anion furnished by an indicator (acid) or cation furnished by indicator (basic) imparts its characteristic colour to solution at point. For example phenolphthalein, the dissociation is underset("Colourless")(H In hArr H^(+))+underset("Pink")(In^(-)), K_(H In)= ([H^(+)][In^(-)])/([H In]) favoured in presence of alkali and pink colour of phenolphalein ion is noticed as soon as the medium changes to alkaline nature. The end point of acid-base neutralisation not necessarily coincides with equivalent point but it is closer and closer to equivalence point. Also at equivalence point of acid-base neutralisation pH is not necessarliy equal to 7. Bromophenol blue is an acid indicator having dissociation constant 5.84xx10^(-5) . The percentage of coloured ion furnished at a pH of 4.84 is:

During neutralisation of an acid by a base, the end point refers for the completion of reaction. The detection of end point in acid -base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthlein) or a weak base (Mrthyl orange). At about 50% ionisation which depends on the medium, the anion furnished by an indicator (acid) or cation furnished by indicator (basic) imparts its characteristic colour to solution at point. For example phenolphthalein, the dissociation is underset("Colourless")(H In hArr H^(+))+underset("Pink")(In^(-)), K_(H In)= ([H^(+)][In^(-)])/([H In]) favoured in presence of alkali and pink colour of phenolphalein ion is noticed as soon as the medium changes to alkaline nature. The end point of acid-base neutralisation not necessarily coincides with equivalent point but it is closer and closer to equivalence point. Also at equivalence point of acid-base neutralisation pH is not necessarliy equal to 7. The dissociation constant of an acid-base indicator which furnishes coloured cation is 1xx10^(-5) . The pH of solution at which indicator will furnish its colour is :

During neutralisation of an acid by a base, the end point refers for the completion of reaction. The detection of end point in acid -base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthlein) or a weak base (Mrthyl orange). At about 50% ionisation which depends on the medium, the anion furnished by an indicator (acid) or cation furnished by indicator (basic) imparts its characteristic colour to solution at point. For example phenolphthalein, the dissociation is underset("Colourless")(H In hArr H^(+))+underset("Pink")(In^(-)), K_(H In)= ([H^(+)][In^(-)])/([H In]) favoured in presence of alkali and pink colour of phenolphalein ion is noticed as soon as the medium changes to alkaline nature. The end point of acid-base neutralisation not necessarily coincides with equivalent point but it is closer and closer to equivalence point. Also at equivalence point of acid-base neutralisation pH is not necessarliy equal to 7. The dissociation constant of an acid-base indicator which furnished coloured anion is 1xx10^(-5) . The pH of solution at which indicator is 80% in dissociated form is:

During the neutralisation of an acid by a base, the end point refers to the completion of reaction. The detection of end point in acid-base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthalein) or a weak base (Methyl orange). At 50% ionisation which depends on the medium. the anion furnished by an indicator (acid) cation furnished colour to solution at end point. For example, phenolphthalein dissociation underset("Colourless")(HIn)toH^(+)+underset("Pink")(In^(-)),K_(HIn)=([H^(+)][In^(-)])/([HIn]) is favoured in presence of alkali and pink colour of phenolphthalein ion is noticed as soon as the medium changes to alkali nature. The end point of acid-base neutralisation not necessarily coincides with eqivalence point but it is closer to equivalence point. Also at equivalence point of acid-base neutralisation, pH is not necessarily equal to 7. Which among the followig statements are correct? (P) At equivalence point of NaOH AND HCI,pH=7 (Q) At equivalence point of NaOH and CH_(3)COOH,pH gt 7 (R) At equivalence point of NH_(4)OH and HCI,pH lt 7 (S) An indicator shows best results if equivalence point is within the pH range pK_(In)pm1 (T) ) At equivalence point of NH_(4)OH and formic acid pH lt 7

During the neutralisation of an acid by a base, the end point refers to the completion of reaction. The detection of end point in acid-base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthalein) or a weak base (Methyl orange). At 50% ionisation which depends on the medium. the anion furnished by an indicator (acid) cation furnished colour to solution at end point. For example, phenolphthalein dissociation underset("Colourless")(HIn)toH^(+)+underset("Pink")(In^(-)),K_(HIn)=([H^(+)][In^(-)])/([HIn]) is favoured in presence of alkali and pink colour of phenolphthalein ion is noticed as soon as the medium changes to alkali nature. The end point of acid-base neutralisation not necessarily coincides with eqivalence point but it is closer to equivalence point. Also at equivalence point of acid-base neutralisation, pH is not necessarily equal to 7. Bromophenol blue is an acid having dissociation constant 5.48xx10^(-5) . The percentage of coloured ion furnished at a ph of 4.84 is :

During the neutralisation of an acid by a base, the end point refers to the completion of reaction. The detection of end point in acid-base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthalein) or a weak base (Methyl orange). At 50% ionisation which depends on the medium. the anion furnished by an indicator (acid) cation furnished colour to solution at end point. For example, phenolphthalein dissociation underset("Colourless")(HIn)toH^(+)+underset("Pink")(In^(-)),K_(HIn)=([H^(+)][In^(-)])/([HIn]) is favoured in presence of alkali and pink colour of phenolphthalein ion is noticed as soon as the medium changes to alkali nature. The end point of acid-base neutralisation not necessarily coincides with eqivalence point but it is closer to equivalence point. Also at equivalence point of acid-base neutralisation, pH is not necessarily equal to 7. The dissociation constant on an acid-base indicator which furnishes coloured anion is 1xx10^(-5) . The pH solution at which indicator will furnish its colour is :

During the neutralisation of an acid by a base, the end point refers to the completion of reaction. The detection of end point in acid-base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthalein) or a weak base (Methyl orange). At 50% ionisation which depends on the medium. the anion furnished by an indicator (acid) cation furnished colour to solution at end point. For example, phenolphthalein dissociation underset("Colourless")(HIn)toH^(+)+underset("Pink")(In^(-)),K_(HIn)=([H^(+)][In^(-)])/([HIn]) is favoured in presence of alkali and pink colour of phenolphthalein ion is noticed as soon as the medium changes to alkali nature. The end point of acid-base neutralisation not necessarily coincides with eqivalence point but it is closer to equivalence point. Also at equivalence point of acid-base neutralisation, pH is not necessarily equal to 7. The dissociation constant of an acid-base indicator which furnishes colorued cation is 1xx10^(-5) . The pH of solution at which indicator will furnish its colour is :

During the neutralisation of an acid by a base, the end point refers to the completion of reaction. The detection of end point in acid-base neutralisation is usually made by an acid-base indicator. An acid-base indicator is itself a weak acid (Phenolphthalein) or a weak base (Methyl orange). At 50% ionisation which depends on the medium. the anion furnished by an indicator (acid) cation furnished colour to solution at end point. For example, phenolphthalein dissociation underset("Colourless")(HIn)toH^(+)+underset("Pink")(In^(-)),K_(HIn)=([H^(+)][In^(-)])/([HIn]) is favoured in presence of alkali and pink colour of phenolphthalein ion is noticed as soon as the medium changes to alkali nature. The end point of acid-base neutralisation not necessarily coincides with eqivalence point but it is closer to equivalence point. Also at equivalence point of acid-base neutralisation, pH is not necessarily equal to 7. Which of the following statements are correct? (P) Phenolphthalein is not a good indicator for weak alkali titrations. (Q) Phenolphthalein does not give pink colour with weak alkalies as NH_(4)OH (R) Phenolphthalein is an basic indicator and imparts colour in basic medium.