What is atomic structure?
The number of protons in an atom, how the protons electrons and neutrons are arranged in the energy shells
What two particles are equal
Protons and electrons
Give the charge on all of the particles
Electrons-negative protons -positive neutron -negative
What is the format of the energy shells
Nucleus containing protons and neutrons and then electrons around in the energy levels
What is the maximum number of electrons in the first shell and second shell ?
2 and 8
The number of electrons is equal to which other particle?
Protons meaning they have no overall charge
What is the number of protons called in an atom?
Atomic number- arranged in the periodic in increasing atomic number
If carbons atomic number is 6 what is the arrangement of electrons
What is ionic bonding?
When atoms with no full outer shell want to gain or loose electrons so they become a noble property and so they become stable, they do this by exchanging electrons with other elements, such as sodium, it has a structure of 2,8,1 so it wants to loose the last electron so it has a full outer shell
How do you present ionic bonding ?
You put the structure in brackets and give them a charge, if the charge is negative it means they have gained an electron and if it is positive it means they have lost an electron.
Do metals form positive or negative ions?
What are the ionic bonds also know as?
Strong electrostatic forces of attraction between oppositely charged ions.
What can you say about ionic compounds melting and boiling points?
They are very high
What would happen to the structure of chlorine (2,8,7) in ionic bonding?
It would gain an electron and become Cl- (2,8,8)-
What is covalent bonding?
Where two non metals share electrons to act as a full outer shell making them become noble and have a stable structure.
What are some properties of covalent compounds?
They are small molecules with low melting and boiling points and they are usually gases
What do covalent bonds also form ?
Giant structures such as diamond and graphite
Describe the bonding in metals:
Arranged in regular layers, positively charged ions form the core and their outer negative electrons form the sea of electrons also know as delocalised electrons which help the metal conduct electricity as they carry the current as the drift around, there is a neutral electrostatic attraction between the positive and negative ions
Give two properties of giant metallic structures?
Malleable and ductile
What are simple molecules?
They are molecules with no overall charge, they contain strong covalent bonds but weak intermolecular forces, they have low melting and boiling points.
What are ionic compounds?
They have an electrostatic attraction and they are held together in a lattice, between a metal and non metal, conduct electricity an they have a high melting and boiling point.
What are macro molecules also known as?
Giant covalent substances
What are some examples?
Graphite, diamond and silica
Why can graphite conduct electricity?
Because it contains delocalised electrons and it's arranged in layers which slide over each other.
What are fullerenes and give an example?
They are carbon giant structures and they where only recently discovered e.g bucket ball
What is the size of nano science ?
What are uses of nano science?
Self cleaning titanium oxide glass, nano silver particles in socks to stop odour
What are possible dangers of nano science?
We don't know long term effects, they are so small they can absorb into the body
When fullerenes are joined together what do they form?
Nanotubes which conduct electricity
Give an example of a redox reaction.
Copper oxide + carbon --> carbon dioxide + copper
The copper oxide to copper is reduction
The carbon to carbon dioxide is oxidation
What is oxidation?
Gaining oxygen or loosing electrons
What is reduction?
Loosing oxygen or gaining electros
What is electrolysis?
The process in which ionic substances are broken down into simpler substances using electricity.
What does the substance have to be in to ensure the ions can move freely?
Molten form or in solution
What is the electrolyte?
The liquid that contains the free ions which conduct electricity
What is the negative electrode called?
What is the positive electrode called?
What reaction happens to the positively charged ions?
They move to the anode, they receive electrons and are reduced
What happens to the negatively charged ions?
The move to the cathode, they loose electrons and are oxidised.
What is the balanced equation that takes place at the anode?
2O2- - 4e- --> O2
What is the balanced equation that takes place at the cathode?
Al3+ + 3e- --> Al
What are some uses of aluminium ?
Packaging due to low density, air craft body's as light but strong, headlamp reflectors as it reflects light
What are some properties of titanium?
High melting point strong and resistant to corrosion
What are the four types of steel.
-low alloy steels
-high alloy steels
What is relative atomic mass? Ar
All atoms compared to carbon12 just the atomic number
What is relative molecular mass? Mr
Relative formula mass, you add all individual atomic masses together
What is the empirical formula?
The simplest RATIO, find the masses, find the atomic mass, divide masses by atomic mass, simplify.
What is percentage yeild?
How much product is made compared to the 100%
What's the formula for percentage yeild?
(Ar x number of atoms) / mr x 100
Why don't you get 100% yeild?
the reaction may be reversible
May not be pure, may be left on apparatus.
What does the symbol of an equilibrium arrow indicate?
A reversible reaction
What happens when you reach equilibrium ?
The forward and the backward reaction are at the same rate, they level out.
What is the process that makes ammonia?
The harder process
What two things make ammonia and where are the from?
Nitrogen from the air and hydrogen from methane.
What is the equation for ammonia ?
N2 + 3H2 <---> 2NH3
How do you stop backward reaction in this process?
Temp is at 450 degrees, pressure is at 200 atm and hydrogen and nitrogen is passed over an iron catalyst.
What do these conditions provide?
An optimum condition
What are some advantages of fertilisers?
The provide a better yeild, More profitable farming and it improves soil condition
Eutrophication, can make streams and rivers acidic,
What is a test for ammonia?
Damp red litmus will turn the blue as ammonia is the only alkaline gas
What are nearly all the compounds in crude oil ?
Hydrocarbons containing hydrogen and carbon
What iOS the general formula for Alan's?
Cn + H2n + 2
What are alkanes?
Saturated hydrocarbons containing single bonds
What are the first four alkanes and what are their formula?
Butane - c4h10
What is catalytic cracking and what does is produce?
How alkanes are broke down, large hydrocarbon molecules broken down into smaller molecules using a catalyst whi h produces a mixture of smaller alkanes & alkenes
What are alkenes?
They are formed by cracking, the they can be made into polymers and then are unsaturated hydrocarbons that contain double bonds
What is the general formula for alkenes?
What are the first three alkenes and what is their formula?
What is a test to distinguish betweens saturated and unsaturated compounds?
Red bromine water- in the presence of unsaturated compounds the bromine water decolourises
Whar are polymers?
Large molecules that are made when monomers are joined together to form long chains, held together by covalent bonds
What are many polymers made from?
What is polymerisation?
Turning monomers into polymers
Ethene --> polythene
What must you do to the double bond?
Break it, and put the repeating unit in brackets with an n next to it.
What are some properties of plastics?
They don't conduct electricity, poor conductors of heat, very unreactive, persist I the environment for a long time .
What do the properties of plastics depend on?
How the chains are made
What are branching chains?
Chains that give the properties: light soft and easy to melt such as plastic bags
What are lined up chains?
Chains that give the properties: dense, rigid and hard to melt e.g bins- hard plastics
What factors effect properties of plastics?
Reaction conditions, monomersm additives
What are thermosoftening plastics?
Plastics that are solid when cols, they can be moulded into shapes, they have weak intermolecular forces for example carrier bags and natural rubber
What are thermosetting plastics?
Cannot be stretched, high melting points, they are strong rigid and brittle, they have strong intermolecular forces, for example; hard plastic chair
What are the three ways to dispose waste plastics?
Landfill incineration and recycling.
What's and advantage of landfill ?
Convinient, it's possible to extract and cell methane from
Bin lorries create noise and traffic pollution, potential for environmental damage, expensive
Advantage for incineration?
Burns all the rubbish away
Advantage for recycling?
Uses less water and energy, fewer green house gases
Storing, sorting and cleaning is expensive, risk on contamination
What are the three main plastics that can be recycled?
PET- oven metal trays
HDPE- milk bottles
PVC- shampoo bottles
Why use biodegradable plastics?
Better for the environment as plastics can be broken down and converted in to CO2 water and minerals by micro organisms
What are smart materials?
Materials that have properties that can react to change with their environment e.g pressure temperature and light.
What are shape memory alloys ?
Alloys that can change shape easily when heated, used in spectacle frames
What are thermochemistry materials?
They change colour with the temperature used in food packaging
What are photochromic materials?
Change colour according to light intensity, e.g security markers
What are polymer gels?
Have the ability to absorb or expel water used in nappies
What does the term solvent mean?
The liquid the solute dissolves in
What does solute mean?
The substance that dissolves in a liquid to form a solution
What does solution mean?
The mixture formed when a solute has dissolved in a solvent
A substance that will dissolve
A substance that won't dissolve.
No more solute can dissolve
How can solubility be increased?
By increasing temperature, adding more solvent and stirring.
What's a solubility curve?
Helps predict the mass of solute that will dissolve in a particular mass of a solvent at a certain temperature
What's hard water?
Water that contains minerals and salts that have been dissolved in the water
Whats an advantage if hard water?
People prefer the taste, it's good for children, helps redue heart illness
Scale forms inside kettles, can clog pipes
What is an experiment to distinguish between hard and soft water?
How much soap is needed to form a lather when the water is shaken
What is water treatment also know as?
What are the stages?