Zadanie 2e
Wzorowane na: Chemistry HL Paper 2, May 2023, TZ1, pytanie 2(e). Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Polecenie
The oxidation of sulfur dioxide in industry requires a catalyst.
(i) State how a catalyst increases the rate of this reaction.
(ii) Sketch a Maxwell-Boltzmann distribution curve showing the activation energies with and without a catalyst.
(iii) Suggest how the progress of the reaction could be monitored.
Sprawdź rozwiązanieUkryj rozwiązanieKlucz i punktacja
Odpowiedź z klucza
(i) provides an alternative reaction pathway with a lower activation energy ✔
(ii) correct shape of curve: starts at the origin, rises to a single peak and falls with a long tail that does not touch the x-axis at high energy ✔
Ea(catalysed) marked on the x-axis at a lower energy than Ea(uncatalysed) ✔
(iii) measure the change in pressure / volume «the amount of gas falls from 3 mol to 2 mol»
OR temperature
OR concentration of SO2 / O2 / SO3 ✔
Schemat punktowania
(i) [1]: both 'alternative pathway' and 'lower activation energy' are needed. (ii) [2]: M1 curve shape, M2 two activation energies marked with the catalysed one lower; ignore any shading under the curve. (iii) [1]: accept any valid method that follows a quantity changing during the reaction; do not accept pH.