Zadanie 4a
Calculate the pH of a 0.125 mol dm−3 solution of sodium hydroxide.
pOH and interconverting pH, pOH, [H+] and [OH-]
Use pOH = -log[OH-] and pH + pOH = 14 at 298 K to convert between [H+], [OH-], pH and pOH in any direction, and calculate the pH of strong base solutions from their concentration.
Tę umiejętność sprawdza 8 zadań wzorowanych na arkuszach IB z lat 2022–2026.
Zadania sprawdzające tę umiejętność: 8 Otwórz w wyszukiwarce z filtrami
Zadanie 3b
(i) Outline the way in which ammonia behaves as a Lewis base during the formation of the complex ion [Ag(NH3)2]+(aq). (ii) Determine the pH at 298 K of an aqueous ammonia solution of concentration 0.180 mol dm−3. Use section 1 of the data…
Zadanie 31
An aqueous solution at 298 K has a pH of 9.20. Kw = [H+][OH−] = 1.00 × 10−14 at 298 K What is the hydroxide ion concentration of the solution, in mol dm−3? A. 6.31 × 10−10 B. 1.58 × 10−9 C.…
Zadanie 3b
Potassium oxide, 0.0150 mol, was dissolved in water and the solution was made up to a final volume of 250.0 cm3. (i) Write a balanced equation for the reaction of potassium oxide with water. (ii) Calculate the pH of the solution.
Zadanie 5c
The ionic product constant of pure water, Kw, is 1.00 × 10−14 at 25 °C and 5.48 × 10−14 at 50 °C. (i) Suggest why the value of Kw for pure water becomes larger as the temperature rises. (ii) Calculate both the pH and the pOH of pure…
Zadanie 5a
The concentration of an ethanoic acid solution was found by titration with a 0.150 mol dm−3 standard solution of potassium hydroxide, KOH(aq), using an indicator to detect the end point. (i) Calculate the pH of the potassium hydroxide solution.…
Zadanie 4c
The base dissociation constant of methylamine at 298 K is Kb = 4.4 × 10−4. (i) Calculate the concentration of hydroxide ions in a methylamine solution with pH = 11.6. Use sections 1 and 2 of the data booklet. (ii) Calculate the concentration, in…
Zadanie 7a
(i) State why ammonia can act as a Lewis base. (ii) Calculate the pH of a 2.50 × 10−2 mol dm−3 aqueous solution of ammonia. pKb = 4.75 at 298 K. (iii) Justify whether a 1.0 dm3 solution made by mixing 0.30 mol NH3…