Ionic Equilibrium

What is the purpose of understanding pH changes in titrations?

To select a suitable indicator

What is the pH range for which phenolphthalein is a suitable indicator?

8.3 to 10.5

Why are different indicators used for different systems in acid-base titrations?

Because indicators are either weak acids or weak bases

What is the ratio of the two forms of indicator that the human eye can detect a colour change?

0.1 to 10

What type of titration does not have a suitable indicator?

Weak acid vs weak base

What is the equilibrium constant for the indicator reaction?

KIn = [H+][In-] / [HIn]

What is the degree of hydrolysis defined as?

The fraction (or percentage) of the total salt which is hydrolysed at equilibrium

What is the hydrolysis constant (Kh) of a weak acid or base?

The equilibrium constant for the reaction of the acid or base with water

What is the purpose of an indicator in an acid-base titration?

To detect the equivalence point of the reaction

What type of salt will undergo hydrolysis in an aqueous solution?

Salts of weak acids and strong bases

What is the relationship between the hydrolysis constant (Kh) and the acid dissociation constant (Ka) and base dissociation constant (Kb)?

Kh = Kw / Kb

What is the colour of the indicator methyl orange in an acidic solution?

Yellow

What is the general equation for the hydrolysis of a salt (BA)?

BA + H2O ⇌ HA + BOH

What is the unit of the hydrolysis constant (Kh)?

no unit

What type of salt does not undergo hydrolysis?

Salt of strong acid and strong base

What is the purpose of an indicator in acid-base titrations?

To determine the end point of the titration

What is the pH range of Cresol red indicator?

1.2 – 1.8

What is the importance of buffer systems in biological systems?

To maintain a constant pH

What is the condition for precipitation to occur in a solution?

Ionic product is greater than the solubility product

What is the purpose of adding a group reagent in qualitative analysis?

To identify the basic radicals in different groups

What is the reason for the precipitation of soap from a solution?

The ionic product of soap exceeds its solubility product

What is the criterion for an electrolyte to be unsaturated?

Ionic product is less than the solubility product

What is the relationship between the ionic product and solubility product in a saturated solution?

Ionic product is equal to the solubility product

What is the process of separating soap from a solution by adding a salt known as?

Salting out

What type of electrolyte is represented by the formula Ksp = [Ag+]2[CrO42-]?

A2 B3 type salt

What is the purpose of adding a concentrated solution of NaCl to a soap solution?

To precipitate soap from the solution

What happens when the ionic product exceeds the solubility product?

The equilibrium shifts towards the left-hand side

What is the condition required for the precipitation of group second radicals such as Pb+2?

Presence of dilute HCl

What is the term for the process of adding an electrolyte to a solution to increase the concentration of one of the ions?

Salting out

What is the term for the product of the concentrations of the ions in a solution raised to their respective stoichiometric coefficients?

Ionic product

What is the term used to describe the product of concentrations of H+ and OH- ions in water at a particular temperature?

Ionic product of water

What type of electrolyte is water, and what is its characteristic?

Weak electrolyte, partially dissociates

What is the reaction between FeSO4 and KCN, resulting in the formation of K4[Fe(CN)6] and K2SO4?

Complexation reaction

What is the term used to describe salts that furnish more than one cation or more than one anion when dissolved in water?

Mixed salt

What is the phenomenon where the solubility of a soap is decreased in the presence of a high concentration of ions?

Salting out of soap

What is the term used to describe the process of neutralization, where an acid and a base react to form salt and water?

Neutralization