GCSE C3 AQA - I can answer any questions you have

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I understand the whole of C3 and i have tonnes of workbooks and textbooks so i can answer any questions you may have for the exam :)

Posted: 24-05-11 16:23 by Lauren Jade Tutchener

What if I asked you the meaning of my existence....What would you say?

:D

Posted: 24-05-11 17:23 by Mary

its not on the syllabus :)

Posted: 24-05-11 17:55 by Lauren Jade Tutchener

Lauren Jade Tutchener wrote:

its not on the syllabus :)

Hahaha! lol :)

In C3 when you have to work out the empirical formulae using the mass of the material. ehy do you have to times one of them by two? :) x

Posted: 24-05-11 18:51 by Edward Pinches

Can you explain all the required tests with results?

Posted: 24-05-11 19:57 by Bertie Rowbotham

Flame Test (cations)
-steralise wire loop

- add compound

- put into a roaring firs

-identify colour

Bright red = lithuim

golden yellow = sodium

lilac = potassium

brick red = calcium

green = barium

BONDS

double bonds turn bromine water colourless when heated (unsaturated)

single bonds turn bromine water orange/brown when heated (saturated)

TEST FOR CATIONS

add sodium hydroxide

calcium, aluminium and magnesium = white precipitate (aluminium redissolves when excess is added)

Copper (II) = blue precipitate

Iron (II) = green precipitate

TEST FOR ANIONS

add dilute nitric acid then silver nitrate
chlorine = white precipitate

bromide = cream precipitate

iodide = yellow precipitate

if nothing happens star another test with the chemical add dilute HCL and barium chloride
sulfate = white precipitate

TEST FOR AMMONIA

mix with aluminium powder then add sodium hydroxide and heat

if ammonia is made the compound was nitrate
ammonia is tested usiing red litmus paper

Posted: 24-05-11 22:38 by Lauren Jade Tutchener

The ones needed for the exam today was

NITRATE and SULPHATES, Im pretty sure I got them, what did you guys get ?

Posted: 25-05-11 19:40 by Frenchie

Nitrate - add NaOH + a little Al powder = white precipitate

Sulphate- add NaOH + BaCl = white precipitate

For the titration did you get 0.128 (something along those lines), although I assumed it was a 1-1 reaction so I put 0.064

Finally did everybody get CH2 ?!

Posted: 25-05-11 20:26 by Miranda

yup i put 0.128 because i doubled (nh3)2, or whatever it was , to get a 1:2 !! Titration was altogether 5 marks??

empirical formula CH2 worth 3 marks :D

Posted: 26-05-11 22:45 by Frenchie

can you tell me the c2 and b2 2011 markscheme or unofficial markscheme

Posted: 28-05-11 13:20 by Jatinder