topic 10

• For cations do flame test, precipitation reaction or ammonia test
• Add more sodium hydroxide to calcium and aluminium
• silver iodide is yellow
• silver bromide is cream colour
• silver chloride is white
• iron2 is green precipitate with hydroxide
• with Hydroxide iron3 has a precipitate colour of brown
• nitrates and ammoniums always dissolve
• hyroxide, oxide and carbonate rarely dissolve
• copper has a precipitate colour of blue
• damp red litmus paper and ammonia present if blue
• Lithium burns red
• potassium burns lilac
• copper burns blue-green
• sodium burns a yellow colour
• calcium burns orange-red
• magnesium burns white
• Test for carbonate is adding dilute acid
• if carbonate is present bubbles will form
• add dilute hydrochloric acid and then barium chloride solution to test tube
• Positive result is white precipitate if insoluble barium sulphate produced
• halide test is adding nitric acid and then add silver nitrate
• Nanoparticles can catalyse reactions more efficiently because of large surface area : volume ratio
• nanoparticles may become dangerous
• nanoparticles can enter body cells or transport toxic chemicals to areas of the body where they are not needed
• Thermosoftening melts when heated
• thermosetting doesn't melt but sets when heated
• Composites are made from 2 or more materials
• Matrix binds them together
• Reinforcements are the fibres or fragments
• composites : fibre glass, plywood, concrete and carbon fibre
• Borosilicate glass is made from sand and boron trioxide, is harder to melt and break
• Soda lime glass made from sand, sodium carbonate and calcium carbonate
• Glasses can be used as insulators because they have no gaps between particles so heat cannot pass through easily