Electrochemistry Flashcards Preview

Physical chemistry > Electrochemistry > Flashcards

Flashcards in Electrochemistry Deck (10):
1

Why is platinum used?

Provides a surface for the reaction

2

What is a salt bridge?

U shaped tube that contains a salt solution to keep charges balanced

3

Define standard cell potential

Voltage measured when half cell is connected to a standard hydrogen half cell under standard conditions

4

What is EMF?

Potential difference between anode and cathode

5

What is the calculation?

Substract more negative Ecell from more positive
Reduction at more positive (cathode)
Oxidation at more negative (anode)

6

Describe feasibility

Cell potential > 0.4v
REDOX reaction only feasible if species that's more positive is able to be reduced
Limitation - not standard conditions or reaction occurs too slowly it doesn't appear to happen

7

Describe reasoning

X has more -ive E so X redox Eq has greater tendency to lose electron and moves to left
X eqm releases electron into wire, flow to Y which gains electron and Eq moves to right

8

What species acts as a more powerful oxidising agent?

More positive

9

What makes Ecell smaller?

Ag+/Ag more positive

10

Name two advantages of fuel cells and two disadvantages

Non-polluting
/greater efficiency
difficult to store
flammable