Zadanie 21
Wzorowane na: Chemistry SL Paper 1, November 2022, pytanie 21. Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Polecenie
A voltaic cell is based on the reaction
Zn(s) + Ni2+(aq) → Zn2+(aq) + Ni(s)
The half-cells are connected by a salt bridge containing aqueous potassium nitrate. What happens when the cell operates?
A. Electrons flow from Ni to Zn; anions in the salt bridge move towards the Ni half-cell
B. Electrons flow from Zn to Ni; anions in the salt bridge move towards the Ni half-cell
C. Electrons flow from Zn to Ni; anions in the salt bridge move towards the Zn half-cell
D. Electrons flow from Ni to Zn; anions in the salt bridge move towards the Zn half-cell
Sprawdź rozwiązanieUkryj rozwiązanieKlucz i punktacja
Odpowiedź z klucza
C ✔
«zinc is oxidized at the anode (Zn → Zn2+ + 2 e−), so electrons leave through the external circuit towards nickel; positive Zn2+ ions build up in the zinc half-cell, so anions from the salt bridge move into it to keep the solution neutral»
Schemat punktowania
One mark for the correct option.