Electrochemistry A2 Flashcards
What is meant by an ionic equation
An ionic equation which involves all ions which changes state during the reaction
What is a salt bridge and give an example of a solvent
Piece of filter paper alloying ions to cross the boundary, most common solvent is KNO3
Which electrode reduces
Positive electrode
Which electrode oxidises
Negative electrode
What are standard conditions
298 K, a pressure of 1 atm and with all species in solution having a concentration of 1.0 moldm-3
What are the potentials of different solvents compared to
The hydrogen electrode
Describe the standard hydrogen electrode
Hydrogen is bubbled through H+ ions against a piece of platinum metal
What does a higher E value mean (electrode and redox)
More likely to reduce, so is on the positive electrode
How are cells represented
Single line between phase boundary, double line between salt bridge
What is on the RHS on a cell representation
Higher E value
What is a fuel cell
A cell that can produce an electric cell and doesn’t need to be recharged
What is the positive electrode equation for the lithium ion cell
Li+ + CoO2 + e– → Li+[CoO2]–
What is the negative electrode equation for the lithium ion cell
Li → Li+ + e–
What is a fuel cell
A cell that can produce an electric cell and doesn’t need to be recharged
What is the positive electrode equation for the alkaline hydrogen-oxygen fuel cell
O2 + 2H2O + 4e- → 4OH-
