Zadanie 1e
Many rechargeable batteries use an alkaline electrolyte. In the nickel-cadmium cell, cadmium, Cd, is the anode. Cd(OH)2(s) + 2 e− → Cd(s) + 2 OH−(aq) E⊖ = −0.81 V…
Anode, cathode and electrode polarity
Identify the anode as the site of oxidation and the cathode as the site of reduction in any electrochemical cell, and assign electrode signs: anode negative and cathode positive in a voltaic cell, the reverse in an electrolytic cell.
Tę umiejętność sprawdza 26 zadań wzorowanych na arkuszach IB z lat 2022–2026.
Zadania sprawdzające tę umiejętność: 26 Otwórz w wyszukiwarce z filtrami
Zadanie 3d
Iron and nickel can be used to design a voltaic cell. Fe(s) + Ni2+(aq) → Fe2+(aq) + Ni(s) (i) Annotate the diagram with the appropriate electrodes, electrolyte solutions and the direction of electron flow. (ii) The redox reactions in some voltaic…
- Materiał graficzny
Zadanie 20
Which option describes the electrode reactions in a hydrogen fuel cell with an acidic electrolyte? 2 H2(g) + O2(g) → 2 H2O(l) A. Cathode: hydrogen is oxidized; anode: oxygen is reduced B. Cathode: oxygen is reduced; anode: hydrogen is oxidized C.…
Zadanie 34
Which combination is correct for this cell, when nickel is more reactive than silver? A. Cathode: silver; anode: nickel; sign on cathode: -; sign on anode: + B. Cathode: nickel; anode: silver; sign on cathode: -; sign on anode: + C. Cathode: nickel; anode:…
- Materiał graficzny
Zadanie 39
What occurs during the operation of a galvanic cell containing zinc, Zn, and nickel, Ni? Zn(s) ∣ Zn2+(aq) ∣∣ Ni2+(aq) ∣ Ni(s) I. Zinc atoms are oxidized at the anode II. Electrons flow through the external circuit from the nickel electrode to the zinc…
Zadanie 3c
In a molten carbonate fuel cell the mixture of hydrogen and carbon dioxide from the reaction is fed to the anode, while a mixture of oxygen and carbon dioxide is fed to the cathode. Carbonate ions, CO32−, move through the molten electrolyte from the…
- Materiał graficzny
Zadanie 37
Molten lead(II) bromide, PbBr2(l), is electrolysed using inert electrodes. Which products form at the electrodes? A. Anode: Br2, cathode: Pb B. Anode: O2, cathode: Pb C. Anode: Pb, cathode: Br2 D. Anode:…
Zadanie 3a
Below is a sodium-ion cell as it discharges, supplying a current to an external circuit. The anode is sodium held in a lattice of hard carbon and the cathode is iron(III) phosphate, FePO4, which is converted to NaFePO4 as the cell discharges.…
- Materiał graficzny
Zadanie 7c
Molten potassium iodide is electrolysed. Write the half-equation for the reaction at each electrode: the positive electrode (anode) and the negative electrode (cathode).
Zadanie 7e
The diagram shows a voltaic cell made from a zinc half-cell and a copper half-cell. The salt bridge contains aqueous potassium nitrate, KNO3(aq). Electrons flow through the external circuit in the direction shown. Use section 19 of the data booklet to…
- Materiał graficzny
Zadanie 29
Which statement is correct for a voltaic cell made from a zinc half-cell and a copper half-cell? The standard electrode potential of the zinc half-cell is more negative than that of the copper half-cell. A. Zinc is the cathode. B. Electrons flow through the…
Zadanie 31
Zinc lies above nickel in the reactivity series. A voltaic cell is made from a zinc electrode in Zn2+(aq) and a nickel electrode in Ni2+(aq). The electrodes are connected by a wire with a voltmeter, and the two solutions are connected by a salt…
- Materiał graficzny
Zadanie 8a
The diagram shows the apparatus. The left-hand half-cell is the anode and the right-hand half-cell is the cathode; the electrodes and solutions are not labelled. State which electrode and which solution are in each half-cell, and state the direction of…
- Materiał graficzny
Zadanie 29
A voltaic cell is constructed from a half-cell of metal M in a solution of M2+ ions and a half-cell of metal N in a solution of N2+ ions. The half-cells are joined by a salt bridge and an external wire.…
Zadanie 2b
Sketch the voltaic cell that would produce the greatest cell potential (EMF) using the metals and solutions in this experiment. On your diagram label the metal and the solution in each half-cell, the anode, the cathode, the salt bridge and the direction of…
Zadanie 3a
A dilute aqueous solution of potassium iodide, KI(aq), is electrolysed using inert graphite electrodes, as shown in the diagram. (i) State the direction in which the electrons move in the external circuit, and the direction in which the positive ions and the…
- Materiał graficzny
Zadanie 4b
(i) Outline why electrons flow from the iron half-cell to the copper half-cell when the two are connected by a wire. Use section 19 of the data booklet. (ii) Formulate equations for the reactions taking place at the anode (negative electrode) and at the…
Zadanie 29
Which row describes an electrolytic cell? A. The anode is positive; the overall reaction is non-spontaneous B. The anode is negative; the overall reaction is spontaneous C. The anode is negative; the overall reaction is non-spontaneous D. The anode is…
Zadanie 30
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…
Zadanie 31
A voltaic cell is assembled from the two half-cells below, connected by a salt bridge. Which statement is correct? A. Anions move from the salt bridge into the magnesium half-cell B. Anions move from the salt bridge into the copper half-cell C. Electrons flow…
- Tabela do uzupełnienia
Zadanie 5b
Aluminium is produced industrially by the electrolysis of aluminium oxide dissolved in molten cryolite, as shown in the diagram. (i) Outline why the molten mixture is considered to be an electrolyte. (ii) Identify the electrode at which aluminium forms and…
- Materiał graficzny
Zadanie 5b
Aluminium is produced by the electrolysis of molten aluminium oxide (in industry dissolved in molten cryolite to lower the operating temperature). A simplified cell is shown in the diagram. (i) Outline why the molten mixture is classified as an electrolyte.…
- Materiał graficzny
Zadanie 15a
Some bacteria oxidize propanoate ions, CH3CH2COO−(aq), to carbon dioxide gas at the negative electrode of a microbial fuel cell. Air is supplied to the positive electrode and the cell operates in acidic conditions. Deduce the half-equation for the…
Zadanie 29
A battery is connected in a circuit. The arrows show the direction of electron flow. What does terminal X of the battery represent? A. Anode and positive terminal B. Anode and negative terminal C. Cathode and positive terminal D. Cathode and negative terminal
- Materiał graficzny
Zadanie 30
What are the products when dilute aqueous sodium sulfate is electrolysed using inert electrodes? E⊖(Na+∣Na) = −2.71 V Choose the products at the anode (positive electrode) and at the cathode (negative electrode). A. Anode:…
Zadanie 28
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…