Separate Chemistry 2 Flashcards
What colour will lithium go in a flame test?
Red (crimson)
What colour will sodium go in a flame test?
Yellow
What colour will potassium go in a flame test?
Lilac
What colour will Calcium go in a flame test?
Orange-red
What colour will Copper go in a flame test?
blue-green
What colour will Aluminium go in the precipitate test?
White at first, but redissolves in excess NaOH to form a colourless solution.
What colour will Calcium go in the precipitate test?
White
What colour will Copper go in the precipitate test?
Blue
What colour will Iron 2+ go in the precipitate test?
Green
What colour will Iron 3+ go in the precipitate test?
Brown
How can you test for ammonium ions?
Add NaOH and gently heat. Hold a piece of damp red litmus and if it is ammonia, it will turn blue.
What do you add to test for halide ions?
Silver Nitrate and nitric acid
What colour will chloride ions go when silver nitrate is added?
Gives a white precipitate of silver chloride
What colour will bromide ions go when silver nitrate is added?
Gives a cream precipitate of silver bromide
What colour will iodide ions go when silver nitrate is added?
Gives a yellow precipitate of silver iodide
How do you test for carbonate ions?
Add dilute acid, if it fizzes, it is a carbonate.
How do you test for sulfate ions?
Add dilute HCl then add barium chloride. If a white precipitate of barium sulfate if formed, it is a sulfate ion.
What is flame photometry?
An instrumental method that allows you to identify ions in a dilute solution.
Give 3 advantages of using machines to analyse unknown substances.
Very sensitive, very fast, very accurate.
How big are nanoparticles?
1-100nm
Are nanoparticles bigger or smaller than atoms?
Bigger, nanoparticles typically contain about 100 atoms.
Do nanoparticles have a high or low surface area to volume ratio?
High
Give some uses of nanoparticles.
Catalysts, cosmetics, nanomedicine, lubrication, electric circuits, sports equipment and wound dressings (silver nanoparticles)
Why could nanoparticles be dangerous?
Some nanoparticles used in medicine don’t break down easily so they could start to build up in cells, could cause lung inflammation if breathed in.
Give 2 properties of ceramics.
Stiff but brittle
What is clay and what are its properties?
A mineral formed from weathed rock. It is soft when dug up which makes it easy to mould. Can be hardened at high temperatures making It ideal for building.
What is glass and what are its properties?
Generally transparent and strong and can be moulded when hot. Most glass is soda-lime glass which is made by heating limestone, sand and sodium carbonate.
Give 2 examples of composite materials.
Fibreglass and concrete.
How is carbon fibre made?
Carbon atoms are bonded together to make carbon fibres or carbon nanotubes held together in a polymer resin.
