Advertisements
Advertisements
Question
Answer the following :
The pH of rainwater collected in a certain region of Maharashtra on a particular day was 5.1. Calculate the H+ ion concentration of the rainwater and its percent dissociation.
Solution
Given: pH of rainwater = 5.1
To find:
i. H+ ion concentration
ii. Percent dissociation
Formula:
i. pH = -log10[H3O+]
ii. Percent dissociation = α × 100
Calculation: From the formula (i),
pH = -log10[H3O+]
∴ log10[H3O+] = -5.1
= -5 - 0.1 + 1 - 1
= (-5 - 1) + 1 - 0.1
= -6 + 0.9 = `bar(6).9`
∴ [H3O+] = Antilog10[`bar(6).9`]
= 7.943 × 10-6 M
Considering that the pH of rainwater is due to the dissociation of a monobasic strong acid (HA), we have
\[\ce{HA_{(aq)} + H2O_{(l)} -> H3O^+_{ (aq)} + A^-_{ (aq)}}\]
∴ [H3O+] = α
α = `7.943 xx 10^-6`
From formula (ii),
Percent dissociation = `7.943 xx 10^-6 xx 100 = 7.943 xx 10^-4`
i. H+ ion concentration is `7.943 xx 10^-6` M
ii. Percent dissociation is `7.943 xx 10^-4`.
APPEARS IN
RELATED QUESTIONS
The concentration of hydrogen ion in a sample of soft drink is 3.8 × 10–3 M. what is its pH?
Calculate the pH of the following solution:
0.3 g of NaOH dissolved in water to give 200 mL of solution.
Calculate the pH of the following solution:
1mL of 13.6 M HCl is diluted with water to give 1 litre of solution.
The degree of ionization of a 0.1M bromoacetic acid solution is 0.132. Calculate the pH of the solution and the pKa of bromoacetic acid.
If 0.561 g of KOH is dissolved in water to give 200 mL of solution at 298 K. Calculate the concentrations of potassium, hydrogen and hydroxyl ions. What is its pH?
Choose the most correct answer:
The pH of 10-8 M of HCl is ______.
Answer the following in one sentence :
Calculate the pH of 0.01 M sulphuric acid.
In NaOH solution [OH–] is 2.87 × 10–4. Calculate the pH of the solution.
Define pOH.
Derive the equation pH + pOH = 14.
Which of the following is INCORRECT statement?
Which of the following when dissolved in water results in neutral solution?
Which of the following is CORRECT for an aqueous solution of NH4CN?
[Ka of HCN = 4.0 × 10−10, Kb for NH4OH = 1.8 × 10−5]
The pH of an aqueous solution is Zero. The solution is ____________.
The concentration of hydroxide ion in a water sample is found to be 2.5 × 10−6 M. Identify the nature of the solution.
A lab assistant prepared a solution by adding a calculated quantity of HCl gas at 25°C to get a solution with [H3O+]= 4 × 10−5 M. Is the solution neutral (or) acidic (or) basic.
50 ml of 0.05 M HNO3 is added to 50 ml of 0.025 M KOH. Calculate the pH of the resultant solution.
The aqueous solution of sugar does not conduct electricity. However, when sodium chloride is added to water, it conducts electricity. How will you explain this statement on the basis of ionisation and how is it affected by concentration of sodium chloride?
Assertion (A): Increasing order of acidity of hydrogen halides is \[\ce{HF < HCl < HBr < HI}\]
Reason (R): While comparing acids formed by the elements belonging to the same group of periodic table, \[\ce{H - A}\] bond strength is a more important factor in determining acidity of an acid than the polar nature of the bond.
Derive the relationship between pH and pOH.
Define pH.
Calculate the pH of the buffer solution containing 0.5 mol NaF and 0.015 mol HF per litre. [pKa = 3.1427].
Define pOH.
Define pOH.
Define pOH.