Zadanie 30
Wzorowane na: Chemistry HL Paper 1, May 2023, TZ2, pytanie 30. Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
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Polecenie
A standard hydrogen half-cell is connected to a standard Cu2+/Cu half-cell. A voltmeter shows 0.34 V and electrons flow in the external circuit from the hydrogen half-cell to the copper half-cell. Which statement is correct?
A. The hydrogen half-cell is the cathode because it has the more positive electrode potential
B. Reduction takes place in the hydrogen half-cell
C. The standard electrode potential of the Cu2+/Cu half-cell is −0.34 V
D. Hydrogen gas is oxidized and the standard electrode potential of the Cu2+/Cu half-cell is +0.34 V
Sprawdź rozwiązanieUkryj rozwiązanieKlucz i punktacja
Odpowiedź z klucza
D ✔
«electrons leave the hydrogen half-cell, so H2 is oxidized there (the anode); the copper half-cell is the cathode where Cu2+ is reduced, and since the standard hydrogen electrode is defined as 0 V the electrode potential of Cu2+/Cu is +0.34 V»
Schemat punktowania
One mark for the correct option.