Chemical Tests?

We have an ISA tomorrow and I have no idea what it's about but we've been told we should know all of the chemical tests from GCSE to A level. The only one I can remember is the halide test as that was done in the last unit. What other ones are there? I believe there is one with limewater and one where theres a pop but im not entirely sure, and I need to make sure I know every single one off by heart.

Reply 1

*MJ*

2

Aldehyde = Tollens - Silver Mirror

Alkene = Bromine water - Decolourises

Haloalkane = Heat with NaOH, acidify with HNO3, test will AgNO3 - ppt forms depending on halide.

Carboxylic acids = NaHCO3 - CO2 effervesence produced

Acyl Chlorides = AgNO3 - white ppt formed

Different alcohols = Acidified Potassium dichromate and H2SO4 - product will be different for primary, secondary, tertiary.

:smile:

Reply 2

Revolution is my Name

15

The Limewater one is where you pass a gas through Limewater: if it turns cloudy/ a precipitate forms, then that indicates the gas is Carbon Dioxide. The Pop test is where you get the gas in the test tube, then quickly shove a glowing splint in there, and if it pops that indicates the presence of Hydrogen. There's also the test for Unsaturation, which is that Bromine water is turned colourless by a compound if it's unsaturated. Those are all I can think of at the moment.

Reply 3

*MJ*

2

Revolution is my Name

The Limewater one is where you pass a gas through Limewater: if it turns cloudy/ a precipitate forms, then that indicates the gas is Carbon Dioxide. The Pop test is where you get the gas in the test tube, then quickly shove a glowing splint in there, and if it pops that indicates the presence of Hydrogen. There's also the test for Unsaturation, which is that Bromine water is turned colourless by a compound if it's unsaturated. Those are all I can think of at the moment.

Oxygen re-lights a glowing splint, too. :wizard:

Reply 4

thegodofgod

19

Test for Oxygen gas = burn a splint, wave it off so the end goes black, put the black end near oxygen gas and it should light up

Test for chlorine = litmus paper turns red and then the chlorine bleaches the paper white

Reply 5

Ryan03201

what exam board are you with? i know edexcel have a mini specification for the assessed practicals on their website. it contains everything you need to know.