Zadanie 1a
Wzorowane na: Chemistry HL Paper 2, May 2026, TZ3, pytanie 1(a). Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Informacja do zadań 1a-1c.
Metals combine with non-metals to form ionic compounds, many of which are used in industry and in the laboratory.
Polecenie
(i) Magnesium burns in oxygen according to the equation . Explain, using electron configurations, how ions are formed by magnesium and oxygen and how these ions form a compound.
(ii) Explain, using electron configurations, why the element copper, Cu, is an exception to the Aufbau principle.
Sprawdź rozwiązanieUkryj rozwiązanieKlucz CKE i punktacja
Odpowiedź z klucza
(i) Mg: 1s2 2s2 2p6 3s2 AND O: 1s2 2s2 2p4 ✔
Mg loses two electrons AND O gains two electrons
OR
Mg2+ AND O2− formed
OR
both ions have the configuration 1s2 2s2 2p6 ✔
«oppositely charged» ions attract each other electrostatically ✔
(ii) «observed configuration is» [Ar] 4s1 3d10 «and not [Ar] 4s2 3d9» ✔
moving one 4s electron into the 3d sublevel gives a more stable arrangement
OR
a completely filled 3d sublevel is particularly stable ✔
Schemat punktowania
(i) M1: configurations of both atoms (condensed forms accepted); M2: two electrons transferred, or the ions named, or the noble-gas configuration of the ions; M3: electrostatic attraction between oppositely charged ions. (ii) M1: observed configuration of copper, [Ar]4s1 3d10 (full configuration or an orbital diagram accepted); M2: reason based on the extra stability of a full (or half-full) d sublevel. Stating only that the 4s sublevel is filled before 3d earns no mark.