Zadanie 16
Wzorowane na: Chemistry SL Paper 1, May 2024, TZ1, pytanie 16. Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Polecenie
Which change would decrease the rate of the reaction between zinc and dilute sulfuric acid?
Zn(s) + H2SO4(aq) → ZnSO4(aq) + H2(g)
A. increasing the temperature of the acid from 20 °C to 30 °C
B. grinding the zinc granules into a powder of the same mass
C. using 2.0 mol dm−3 sulfuric acid instead of 1.0 mol dm−3 sulfuric acid
D. replacing the zinc granules with a single lump of zinc of the same mass
Sprawdź rozwiązanieUkryj rozwiązanieKlucz i punktacja
Odpowiedź z klucza
D ✔
«a single lump has a smaller total surface area than the same mass of granules, so fewer zinc atoms are exposed to the acid and the collision frequency, and therefore the rate, decreases; A raises the energy and frequency of collisions, B increases the surface area and C increases the concentration, so these three increase the rate»
Schemat punktowania
One mark for the correct option.