Analytical Chemistry Flashcards
what does pure mean?
A single substance(element or compound) that is not mixed with anything else
What method is used to investigate dyes?
Chromatography
What are rules of Chromatography?
Start line in pencil
Water level below spots
What is the name of the line you mark at the end of chromatography?
Solvent front
How to test for CO(2)
Get a test tube with 2cm of lime water in it
Pour the test tube of carbon dioxide into the lime water
Put a bung on top of it and shake
Turns cloudy
How do you test for hydrogen?
Get a lit splint
Take the bung off the test tube
Hold the splint over the end
Makes a squeaky pop
How to test for oxygen?
Get a glowing splint
Take the bung off the test tube
Hold the splint over the end
Splint relights
How do you test for chlorine?
Hold a piece of damp blue litmus paper at the mouth of the boiling tube with chlorine
The paper turns pink then bleaches white
What is an ion?
A substance with a positive or negative charge on it
What is a cation?
Positively charged ion
What is an anion?
Negatively charged ion
How do you test for cations with sodium hydroxide?
Put 2cm cubes of test solution in a tube and add sodium hydroxide until there is no more changes
Note the colour of the precipitate and whether it dissolves in excess sodium hydroxide
Repeat
How to test for cations using flame tests
Drop the nichrome wire into hydrochloric acid and then the roaring blue flame to clean it
Dip the wire into the solution you want to test then put it in the flame
How to test for carbonates?
Half fill test tube with lime water and place in test tube rack
Put the end of delivery tube into limewater
Add 5cm of hydrochloric acid and add spatula of calcium carbonate
Put the bung on the test tube and observe the limewater
How to test for sulfates?
Pour 2cm of the solution containing the sulfate ion into test tube
Add 1cm barium chloride solution, 1cm hydrochloric acid
