Flashcards
C2
Cards in this deck (33)
- 1Define tensile strengthThe force needed to break a material when it is being stretched
- 2Define compressive strengthThe force needed to squash a material when squeezed
- 3Name 3 properties of metalsShiny, malleable, conductors of electricity
- 4Name three materials that can be made from polymersRubbers, plastics and fibres
- 5What is meant by a synthetic material?A material manufactured using chemical reactions
- 6What is crude oil a mixture of?Hydrocarbons
- 7What is the formula for an alkane?C n H 2n+2
- 8What are the products when an alkane reacts with oxygen?(combustion reaction)Carbon dioxide and water
- 9Give at least two examples of natural materials (materials obtained from living organisms)Cotton, paper, silk, wool
- 10Give the names of the first four alkanesMethane, ethane, propane, butane
- 11How is ethanol made in the chemical industry?By reacting ethene with water
- 12In a fractional distillation column, which end (top or bottom) has the highest temperature?The bottom end has the highest temperature
- 13To what temperature is crude oil heated during fractional distillation?400 degrees C
- 14What happens to the gases as they move up the fractional distillation column?They condense at their boiling point, then they are collected and piped off to be used
- 15What is the process of making polymers called?Polymerisation
- 16What is a polymer made up of?Lots of small, similar molecules called monomers, together
- 17How are different polymers created?Using different monomers or making polymers using more than one type of monomer joined together
- 18Why are synthetic materials often used instead of natural materials?They are cheaper, available in larger quantities and their functions can be adjusted
- 19When are the forces between molecules the strongest?When the molecules are closer together
- 20Why do polymers with stronger forces holding them together have higher melting points?More energy is needed for the bonds to be able to break apart
- 21What does it mean when a substance is highly crystalline?The is a regular pattern of molecules lined up alongside each other.
- 22Give at least two properties of crystalline substancesStrong, high melting point, can be brittle
- 23How does adding a plasticiser alter a substance?It makes it more flexible
- 24How does a plasticiser increase flexibility?Small molecules fit between the polymer molecules, keeping them further apart and therefore weakening the forces between them.
- 25How can cross-linking alter a substance?It makes it rigid, strong, can withstand high temperatures and doesn't soften at all
- 26Give two ways in which crystallinity can be increasedReducing the number of branches on the main polymer chain, making the polymer chains flat and rigid so they can line up neatly
- 27Nanotechnology works with nanoparticles on what scale?From 1-100nanometres
- 28What is a 'buckyball'?An arrangement of 60 carbon nanoparticles in a football shape
- 29Define a catalystA substance that speeds up chemical reactions
- 30How are nanoparticles of titanium oxide used in industry?Used in sunscreen to make it transparent and cleaner on the skin
- 31How are silver nanoparticles used in industry?Used to kill bacteria in hospitals or plastics for food containers
- 32What is the combined material called when nanoparticles are mixed with another material?A composite
- 33What are the possible health hazards of nanotechnology?Nanoparticles could attack nerve cells in the brain or lodge in the lungs but the effects have not been fully investigated
Information
- Description
- GCSE Chemistry Flashcards on C2, created by eecavendish on 30/04/2014.
- Created by
- eecavendish
- Views
- 14
- Rating