Electrochemistry Flashcards
redox reaction
oxidation
reduction
oxidising agent
reducing agent
anode
cathode
electrolyte
Use the table of standard electrode potentials (SEP table) to:
- Predict the chemical species which is oxidised in a redox
reaction and write an equation for the oxidation half-reaction
- Predict the chemical species which is reduced in a redox
reaction and write an equation for the reduction half-reaction
- Write the overall balanced ionic reaction equation by combining
the two half-reactions
- Identify the oxidising agent and the reducing agent for a redox
reaction
- Determine the spontaneity of a redox reaction under standard
conditions
Identify the spectator ion in a redox process and know that the
spectator ion does not take part in the electron transfer
Describe the galvanic cell in terms of:
- self-sustaining electrode reactions
- conversion of chemical energy to electrical energy
Describe:
- the movement of ions through the solutions
- the electron flow in the external circuit of the cell
- the observations in the half-cells
State the functions of the salt bridge as
- completing the circuit
- maintaining electrical neutrality in the half-cells
Describe how the salt bridge maintains electrical neutrality
in the half-cells by referring to the movement of ions in and
out of the salt bridge
State the standard conditions under which standard
electrode potentials are determined
Describe the standard hydrogen electrode and explain its
role as the reference electrode
Know that when used as a reference electrode the standard
hydrogen electrode is connected as the anode (to the
negative terminal of a voltmeter) even though it may not
spontaneously act as the anode
Explain how standard electrode potentials can be
determined using the reference electrode and state the
convention regarding positive and negative values
Galvanic cell theory
State that the galvanic cell has the capacity to deliver
current until the reaction reaches chemical equilibrium or
has run to completion
State that once a galvanic cell reaches chemical equilibrium
or has run to completion the voltage of the cell equals zero
Qualitatively, using Le Châtelier’s principle, predict the
effect of changing concentration on the voltage of a
galvanic cell.
State that increased surface area of the terminals increases
the rate of the reaction which therefore increases the
maximum current that the cell can deliver but does not
affect the emf of the cell
State that the wider, shorter and/or more conductive salt
bridge lowers internal resistance thereby increasing the
maximum current that the cell can deliver but does not
affect the emf of the cell
Describe the electrolytic cell in terms of:
- electrode reactions that are sustained by a supply of electrical
energy
- conversion of electrical energy into chemical energy
Identify or suggest suitable inert electrodes for use in
electrolysis and give reasons for their suitability
Identify the predominant half-reaction taking place at the
anode and cathode during electrolysis of an AQUEOUS
solution