Percentage yield calculations

Chemia IBPaper 2, maj 2026, TZ3wzorowane4 pktobliczenioweśrednie (szac.)

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…

Chemia IBPaper 1A, maj 2026, TZ3wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 19

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 %…

Chemia IBPaper 2, maj 2025, TZ2wzorowane2 pktobliczenioweśrednie (szac.)

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.

Chemia IBPaper 2, listopad 2025, TZ3wzorowane3 pktobliczenioweśrednie (szac.)

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

Chemia IBPaper 1A, listopad 2025, TZ1wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 21

Nitrogen gas is reacted with excess hydrogen gas to produce ammonia. N₂(g) + 3 H₂(g) → 2 NH₃(g) The reaction of 28.0 g of N₂ with excess H₂ produces 25.5 g of NH₃. What is the percentage yield of NH₃? A. 25% B. 50% C. 75% D.…

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 19

Ammonia is oxidized according to the equation below. 4 NH₃(g) + 5 O₂(g) → 4 NO(g) + 6 H₂O(g) What is the amount, in mol, of H₂O produced when 8.00 mol of NH₃ reacts with 5.00 mol of O₂, if the yield is 80 %? A. 4.80 B. 6.00 C. 9.60 D.…

Chemia IBPaper 2, maj 2024, TZ1wzorowane6 pktobliczenioweśrednie (szac.)

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…

Chemia IBPaper 3, listopad 2024wzorowane3 pktobliczeniowetrudne (szac.)

Zadanie 13a

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 M_r…

• Materiał graficzny

Chemia IBPaper 2, listopad 2023, TZ1wzorowane2 pktobliczenioweśrednie (szac.)

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.

Chemia IBPaper 2, listopad 2023, TZ2wzorowane2 pktobliczenioweśrednie (szac.)

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.

Chemia IBPaper 2, maj 2022, TZ1wzorowane5 pktobliczenioweśrednie (szac.)

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

Chemia IBPaper 2, maj 2022, TZ1wzorowane2 pktotwarteśrednie (szac.)

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…