Testing for Negative ions/flame tests

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I find it emtremely hard to learn the tests for all the ions.

Please may someone give me a good way to learn them and memorise them. Its the:

Flame tests - colours and which element they are

Cl- 

Br-

I-

NO3-

SO4-2

CO3-2

Chapter c3 5.1 and 5.2 in Nelson Thornes revision guide

Its under the chapter ANALYSIS in the course

THANK YOU :)

Posted: 24-04-11 14:17 by Georgina

I thought these were precipitation tests?

the flame test are for some metals.

I might b wrong though coz i do a different board

Posted: 24-04-11 15:37 by Pui Pui

Oh my gosh - i have no idea. Well lets just say if anyone has a good way to learn all these type of things is would be really greatful :)

Posted: 24-04-11 17:40 by Georgina

Oh my gosh - i have no idea. Well lets just say if anyone has a good way to learn all these type of things is would be really greatful :)

Posted: 24-04-11 17:40 by Georgina

Well for the flame tests for Li+, Na+ and K+ (which is what i need to know)

Li+ is red

Na+ is orange/yellow

K+ is lilac

If u look on the periodic table these go down Group 1

its like the colours of the rainbow with a big chunk missed out.

also potassium (K) begins with a P like purple but remember ALWAYS write LILAC not purple.

Posted: 24-04-11 18:00 by Pui Pui

For the precipitate reactions in group 7 Cl- Br- and I- they react with silver nitrate to form a precipitate (a solid)

Cl- white precipitate

Br- cream precipitate

I- yellow precipitate

Again these go down the periodic table. Its not too hard to remember which order the colours go in because its gets progressivly darker in colour from white to yellow so cream must be in the middle.

Posted: 24-04-11 18:02 by Pui Pui

Ughh I find it hard to learn these too especially as it was the last topic we did.):. I'll just have to keep repeating it again and again/

Posted: 24-04-11 18:54 by hiuu billy

thankyou :)

i will try band make up some sort of chant to rememeber that :)

Posted: 24-04-11 18:55 by Georgina

The more patterns you see/find the easier it is to remember it. It goes for lots of things in chemistry.

Posted: 24-04-11 19:05 by Pui Pui

Yeah I guess so. The rest of Unit 3 is fine though.

Posted: 24-04-11 19:10 by hiuu billy

bloody hell,it's impossible

Posted: 24-04-11 20:06 by emily

Agreed

Posted: 24-04-11 20:26 by Georgina

Just found this. http://getrevising.co.uk/resources/chemistry_detecting_ions

u can test what u do and don't know so ur not wastng time revising stuff u actually know

Posted: 24-04-11 21:16 by Pui Pui

That's really helpful! Thanskyou 

I may make one aswell as then it will help me memorise them.

There was a question in a past paper - I think it was January 2008 which was a 5 mark question which asked for lots of the tests and results so i completely freaked when i saw it.

Posted: 25-04-11 10:23 by Georgina

I made this and it is quite helpful. I found the handouts that my teacher gave me and turned it into a mini powerpoint :)

hope its useful. feel free to rate and comment XD

http://getrevising.co.uk/resources/helpful_ion_test_powerpoint

Posted: 25-04-11 10:41 by Georgina

Thanks a lot Georgina, that is so helpful. :D.

Posted: 25-04-11 18:27 by hiuu billy

i know, i found the swheets and immediate;y thought i had to put it up.. And by the ratings i guess its helpful. Also, with the print offs from my teacher ive put them on my doors and walls - just an idea :)

Posted: 25-04-11 18:30 by Georgina

AHHHHHH!!!!!!!! HELP!!!!!!

Posted: 23-05-11 18:27 by Chloe Butcher