Calculate the pH of a sample of soft drink whose hydronium ion concentration is 3.8 x 10-3 M.
admin H3O+] = 3.8 x 10-3 pH = – log = – log (3.8 x 10-3) = – (log 3.8 – 3 log 10) = – log 3.8 + 3.0 =…
April 2025
Calculate the pH of 10-8 M HCl.
If we use the relation, pH = – log , we get pH equal to 8. But this is not correct because an acidic solution cannot have pH greater than…
Derive the relationship between Ka and Kb for an acid and its conjugate base.
Conjugate acid and base are related as: Base + H+ <—————> acid Acid <—————–> H+ + base Let us consider a weak acid, HA HA (aq) + H2O < —————>…
Define pH or pH scale.
Sorensen in 1909 discovered a new tern for expressing the concentration of hydrogen ions known as pH or pH scale. The pH of a solution is defined as: The negative…
Calculate the dissociation constant of conjugate base of HF, Ka = 6.8 x 10-4.
We know that HF < ———–> H+ + F– Ka (acid) x Kb (conjugate base) = Kw = 1.0 x 10-14 Ka = 6.8 x 10-4 (given) Kb (F–) =…
What do you mean by Polytrophic acids and bases?
Bronsted acids which can donate more than one proton are called Polytrophic acids or polybasic acids. For example, oxalic acid and sulphuric acid have two ionizable protons per molecule of…
A saturated solution of H2S in water has concentration of approximately 0.10 M. What is the pH of this solution and equilibrium concentrations of H2S, HS– and S2-? Hydrogen sulphide is a diprotic acid and its dissociation constants are Ka1 = 9.1 x 10-8, Ka2 = 1.3 x 10-13 mol L-1 respectively.
The second dissociation constant is very small than the first dissociation constant and therefore, the concentration of H3O+ is obtained only from the first dissociation constant: H2S + H2O <…
What do you mean by Hydrolysis?
Hydrolysis is the interaction of anion or cation of the salt with water to produce an acidic or basic solution. For example: An aqueous solution of copper sulphate is acidic…
Derive the relationship between Kh, Kw, Ka.
Let us consider the concentration of water remains constant, the equilibrium constant for hydrolysis reaction called hydrolysis constant may be written as: Kh = / ………………………………. (1) The following equilibrium…
What do you mean by Indicators?
Indicators are the substances which indicate by change in color, the completion of the chemical reaction. We know that litmus solution is red in the acidic region and blue in…