Zadanie 1b
Potassium also forms compounds with polyatomic ions. 2 KOH(aq) + Cu(NO3)2(aq) → Cu(OH)2(s) + 2 KNO3(aq) (i) 30.0 cm3 of a 0.380 mol dm−3 potassium hydroxide, KOH, solution is mixed with 25.0 cm3 of a 0.310…
Percentage yield calculations
Calculate percentage yield as experimental yield divided by theoretical yield, and solve combined problems involving reacting quantities, limiting reactants and the mass of product actually obtained.
Tę umiejętność sprawdza 10 zadań wzorowanych na arkuszach IB z lat 2022–2026.
Zadania sprawdzające tę umiejętność: 10 Otwórz w wyszukiwarce z filtrami
Zadanie 24
70 dm3 of nitrogen and 150 dm3 of hydrogen are mixed and react to form ammonia; all gas volumes are measured at the same temperature and pressure. N2(g) + 3 H2(g) → 2 NH3(g) What is the percentage yield of ammonia if 66 dm3 is obtained? A. 44 %…
Zadanie 4b
A chemist treated 22.99 g of galantamine with sulfuric acid to make the sulfate salt: 2 C17H21NO3 + H2SO4 → (C17H22NO3)2SO4 The mass of salt isolated was 24.65 g. Determine the percentage yield of the salt. Use section 7 of the data booklet.
Zadanie 3a
(i) If the reaction has a percentage yield of 80 %, calculate the mass, in g, of benzene that would be produced from 2.0 kg of cyclohexane. (ii) Calculate the atom economy for this reaction, as a percentage.
- Materiał graficzny
Zadanie 1a
(i) Determine the limiting reactant when 2.00 g of this powder reacts. (ii) Determine the volume, in dm3, of carbon dioxide released in the reaction in (i) at SATP. Use sections 1, 2 and 4 of the data booklet. (iii) A student collects 0.190…
Zadanie 16a
Ethyl 4-hydroxybenzoate is a preservative used in some oral medicines. It was synthesized by heating 0.745 g of 4-hydroxybenzoic acid with excess ethanol and a few drops of concentrated sulfuric acid as catalyst. C7H6O3 + C2H6O ⇌ C9H10O3 + H2O Mr…
- Materiał graficzny
Zadanie 3b
A student obtained 2.58 g of the ester from 3.00 g of ethanoic acid and an excess of the second reagent. Determine the percentage yield of the ester.
Zadanie 3b
A student heated 3.85 g of propanoic acid with an excess of the second reagent and isolated 3.12 g of the ester. Determine the percentage yield.
Zadanie 1b
In an experiment, calcium turnings were heated strongly in a crucible with a lid. The following data were recorded: (i) Calculate the amount of calcium, in mol, that was used. (ii) Determine the percentage uncertainty in the final mass of product. (iii) Assume…
- Tabela do uzupełnienia
Zadanie 1c
A student heated 3.492 g of calcium turnings in a crucible with a lid and obtained 4.490 g of solid product. If the product is assumed to be calcium oxide only, the percentage yield is 92 %. (i) Evaluate whether the formation of calcium nitride, rather than…