Redox II Flashcards
why do electrochemical cells use redox reaction
the electron transfer between products creates a flow of electrons.
what is the flow of charged particles called
an electrical current that flows between electrodes in the cell
what do most electrochemical cell consist of
two solutions, metal electrodes and a salt bridge
what is a salt bridge
a tube of unreactive ions that move between solutions to carry the flow of charge
what does each half cell have
cell potential which indicate how it will react
What is SHE
measuring standard for half cell potential as it has a cell potential of 0.00v
what are cell potentials measured compared to
to SHE under standard conditions
what does positive potential mean
substance more easily reduced and will gain electrons
what does negative potential mean
substance more easily oxidised and lose electrons become more stable
what are the standard conditions
solutions of 1.0mol dm-3 conc
a temperature of 298k
100 kPa pressure
what does a cell consists
HCl, Hydrogen gas, platinum electrodes
why are plantium electrodes used
metallic, so conduct electricity, but inert so doesn’t interfere with reaction
how should you represent cell in simplified way
The half-cell with the most negative potential goes on the left.
The most oxidised species from each half-cell goes next to the salt bridge.
A salt bridge is shown using a double line.
State symbols are always included.
How do you calculate Emf
E(right) - E(left)
most positive potential minus the most negative potential
what does it mean if overall cell potential is positive
more spontaneous and favourable
