Chemistry C2 AQA Higher Tier Revision Notes

Hey! These are my notes for the Chemistry C2 Exam. I did my exam using these notes in June and got full marks, so feel free to use them! There may be a couple of mistakes with my phrasing of points, and they may not be in sufficient detail for your own usage. 

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  • Created by: Sophie
  • Created on: 14-11-10 14:28
Preview of Chemistry C2 AQA Higher Tier Revision Notes

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Chemistry C2 revision: Exam 26th May 2010
C2 1: Structures and Bonding.
Atomic Structure:
An atoms nucleus contains protons and neutrons.
Electrons orbit the nucleus.
Same number of electrons and protons.
Electrons have a negative charge.
Protons have a positive charge.
Neutrons have no charge ­ neutral.
Overall: positive charge
Type of sub-atomic particle Relative charge
Proton +1
Neutron 0
Electron -1
Number of protons in nucleus = atomic number or proton number
Each element has its own atomic number
The arrangement of electrons in atoms:
One model of the atom: electrons around the nucleus arranged in shells
Each shell: different energy level
Electrons are attracted to the nucleus.
Example of a shell:
Example of electrons in a carbon atom arranged 2,4.
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Chemistry C2 revision: Exam 26th May 2010
Different energy levels can only hold a certain number of electrons;
o First shell = 2 electrons
o Second shell = 8 electrons
o Third shell = 8 electrons.
Elements with a full outer shell are unreactive and stable ­ noble gases.
Horizontal rows ­ periods: as we move one across the electron number increases by one.
Vertical rows ­ groups: elements in a vertical row have similar chemical properties.…read more

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Chemistry C2 revision: Exam 26th May 2010
The force exterted by an ion on the other ions in the lattice acts equally in all directions ­ held
tightly together.
Structure is regular ­ ions packed neatly together
We can represent ionic bonds by dot and cross diagrams -
(shows ionic bonding)
Covalent bonding:
Non metals reacting together.
Can be either simple or giant.…read more

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Chemistry C2 revision: Exam 26th May 2010
Simple molecules:
When two non metals react to form compounds they share electrons in their outer shells
covalent bonds
Low melting and boiling points usually, liquids or gases at room temperature or solids
with low melting points
Covalent substances are strong held tightly together
They are weak intermolecular forces (DO NOT TAKE MUCH ENERGY TO OVERCOME)
They do not conduct electricity as there is no overall charge
Giant covalent substances:
Large network of bonds ­ giant covalent
Substances…read more

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Chemistry C2 revision: Exam 26th May 2010
Type Relative mass
Proton 1
Neutron 1
Electron Negligible
Total number of neutrons and protons is the mass number
Mass number ­ atomic number = number of neutrons, carbon's mass is 12 and its atomic
number is 6. 12 ­ 6 = 6 neutrons
Isotopes: always the same number of protons but can vary in the number of neutrons
Isotope: element with a different neutron number
Sometimes extra neutrons make an atom radioactive, but not all are radioactive.…read more

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Chemistry C2 revision: Exam 26th May 2010
We can use the relative atomic mass (Ar) of element and the relative formulae mass (Mr) of
compounds to help us work out the percentage of an element in a compound.
1. Write down the formula of the compound
2. Using the relative atomic masses work out the relative formula mass of the compound.
Write down the mass of each element of the compound as you work it out.
3.…read more

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Chemistry C2 revision: Exam 26th May 2010
We from this we know that the simplest ratio of atoms is: AlCl3
Equations and calculations:
Chemical calculations can be very useful, but the equation must be balanced in order to be
totally useful.
Making as much as we want:
Rather than talking about the yield in grams we talk about it in the percentage yield.…read more

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Chemistry C2 revision: Exam 26th May 2010
To prevent this we have the ammonia removed by cooling and liquefying as soon as it is
We can then recycle any hydrogen and nitrogen that is left.
N2 + 3H2 = 2NH3
C2 4 ­ Rates of reaction.
How fast?
Rate of reaction how fast a reaction happens
We can measure this by: the mass of a mixture, the volume of gas given off, measure the
light transmitted.…read more

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Chemistry C2 revision: Exam 26th May 2010
High concentration = more collisions
Dissolved particles are closer together therefore more collisions happen in an area of
Concentration is measured in moles per cubic decimetre ­ mol/dm3
Remember: increasing concentration or pressure does not increase the energy with which
the particles collide. It does increase the frequency of the collisions, however.
Sometimes we need to change the rate of a reaction; we can speed up the rate of a reaction
by adding a catalyst.…read more

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Chemistry C2 revision: Exam 26th May 2010
Neutralisation between acids and alkalis is exothermic
Thermal decomposition and photosynthesis are endothermic
C2 6 - Electrolysis
Electrolysis ­ the basics:
Electrolysis means `splitting up using electricity'
In electrolysis we use an electric current to decompose a substance made of ions into
simpler substances.
We call the substance broken down into electrolyte.
The electrode is usually made our of graphite or platinum as they are unreactive.…read more


Former Member

Really good. Good use of diagrams and well organised. However, too make it really engaging and to make it more effective when you or others revise from it use colours and questions to get the people more involved. Well done and thanks for sharing your notes :)!x

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