Zadanie 3e
Wzorowane na: Chemistry HL Paper 2, May 2026, TZ3, pytanie 3(e). Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Informacja do zadań 3a-3e.
Metals and their compounds are used in construction, in batteries and as pigments.
Polecenie
The copper(II) ion, Cu2+, forms a variety of coloured complexes.
(i) Outline, with a reason, why solutions containing [Cu(H2O)6]2+ ions are blue. Use section 15 of the data booklet.
(ii) State the type of bond between the copper(II) ion and water in the complex [Cu(H2O)6]2+.
Sprawdź rozwiązanieUkryj rozwiązanieKlucz CKE i punktacja
Odpowiedź z klucza
(i) the complex absorbs orange light / light of a wavelength in the range 585–647 nm «orange on the colour wheel» ✔
the complementary colour, blue, is transmitted and seen ✔
(ii) coordination bond / dative covalent bond ✔
Schemat punktowania
(i) M1: absorbed light is orange (accept any wavelength within the orange range of section 15); M2: blue is the complementary colour that is transmitted; do not award M2 for "blue light is emitted". (ii) [1]; accept coordinate or dative.
Komentarz
On the colour wheel of section 15 the complement of blue is orange, so orange is the expected absorbed colour. Do not award M2 for "blue light is emitted" or for a colour that is not the complement of the observed one.