Lecture notes

A Level Edexcel Chemistry - Topic 14 - Redox 2/II

1 purchase

Module
Unit 14 - Redox II

Institution
PEARSON (PEARSON)

A Level Edexcel Chemistry - Topic 14 - Redox 2/II Fully updated notes providing drop down answers to self made questions designed from numerous textbooks and exam mark schemes. During my revision, I created these drop down questions and answers by extracting the key information needed to achi...

[Show more]

Preview 2 out of 13 pages

View example

Uploaded on December 26, 2022
Number of pages 13
Written in 2022/2023
Type Lecture notes
Professor(s) N/a
Contains All classes

Topic 14 - Redox 2
Electrochemical cells
What are electrochemical cells made up of?

electrochemical cells are made from two different metals dipped in salt solutions
of their own ions and connected by a wire

Explain the electrodes in an electrochemical cells and what happens at them

electrodes are opposite to electroylsis

anode = negative cathode = positive

oxidation happens at the cathode and reduction at the anode

the more reactive form ions more readily so it gives up its electrons and is
oxidised (so it becomes the anode, where electrons flow from)

the less reactive metal becomes the cathode

Explain the setup and what happens in the zinc/copper electrochemical cell

zinc loses electrons more easily than copper, so in the left half cell, zinc is
OXIDISED to form Zn2+ ions

this releases electrons to the external circuit

in the other half cell, the same number of electrons are taken from the
external circuit, REDUCING the Cu2+ ions to form copper atoms

Describe the purpose of the salt bridge that connects the two half cells

salt bridge is made of filter paper soaked in salt solution - KNO3

the salt ions flow through the salt bridge to complete the cell, and balance out
the chargers in the beakers

Explain how you can have half cells involving solutions of two aqueous ions
of the same element, such as Fe2+ and Fe3+

happens on the surface of the electrode

Topic 14 - Redox 2 1

, neither the reactants or products are solid you use platinum or graphite for the
electrode

it needs to conduct electricity and be very inert so that it wont react with
anything

Electrode potentials
Explain how a potential difference builds up in half cells and relate to the zinc
half cell

as the substances are oxidised or reduced

due to the difference in charge between the electrode and the ions in the
solution

in the zinc half cell, the Zn electrode is negatively charged due to the
electrons left behind wehn ions form and the Zn2+ ions are postively
charged

Explain what the electrode potentials of the half cells determines

the zinc half cell has a more negative E value, so zinc is oxidised(the
reaction goes backwards)

copper is reduced (the reaction goes forward)

Define the standard electrode potential

The standard electrode potential of a half cell is the voltage measured under
standard conditons when the half cell is connected to a standard hydrogen
electrode

Draw how you would set up the apperatus to measure standard electrode
potential with the standard hydrogen electrode

temp = 298K , 25*C

Topic 14 - Redox 2 2

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

You can quickly pay through credit card for the summaries. There is no membership needed.

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller gautamnemani. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for £7.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

68175 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy revision notes and other study material for 15 years now

Start selling