Chemistry paper 6

[Jaxine]

Hello, I was wondering if we have to know about colour of gases or colour of metal or anything because I've seen it in past papers but my teacher never taught me anything about it -_-

 

[Abu mota]

just some basic knowledge, u have to know them by doing practicals but if u dont have practicals in ur school, i dont think u shud worry because they rarely ask about them anyway.

 

[hEbBoOo]

Colour of Gases & Metals or Tests of Gases & Metals?
you dont even need them badly!
but i think you should know about the tests for Metals:
By adding NaOH (Sodium hydroxide solution) on each:
1. Fe (II) Iron --> gives Dirty green precipitate that doesn't dissolve in excess.
2. Fe (III) Iron --> gives Red/Brown precipitate that doesn't dissolve in excess.
3. Ca Calcium --> gives White precipitate that doesn't dissolve in excess.
4. Cu Copper --> gives Blue precipitate that doesn't dissolve in excess.
5. Al Aluminium --> gives White precipitate that DOES dissolve in excess.
6. Zn Zinc --> gives White precipitate that DOES dissolve in excess.
And also for the test of Gases:
1. CO2 Carbon Dioxide --> add lime water it turns to be Milky/Cloudy.
2. H2 Hydrogen --> insert LIGHT splint 'pop' sound is heard.
3. O2 Oxygen --> insert GLOWING splint the splint reglows.
4. NH3 Ammonia --> insert Red litmus paper it turns colour into Blue.
5. Cl2 Chlorine --> Insert litmus paper (any colour) it BLEACHES.
Hope that gives you the information you need and answers you questions!!
Good Luck!

 

[Jaxine]

Colour of Gases & Metals or Tests of Gases & Metals?
you dont even need them badly!
but i think you should know about the tests for Metals:
By adding NaOH (Sodium hydroxide solution) on each:
1. Fe (II) Iron --> gives Dirty green precipitate that doesn't dissolve in excess.
2. Fe (III) Iron --> gives Red/Brown precipitate that doesn't dissolve in excess.
3. Ca Calcium --> gives White precipitate that doesn't dissolve in excess.
4. Cu Copper --> gives Blue precipitate that doesn't dissolve in excess.
5. Al Aluminium --> gives White precipitate that DOES dissolve in excess.
6. Zn Zinc --> gives White precipitate that DOES dissolve in excess.
And also for the test of Gases:
1. CO2 Carbon Dioxide --> add lime water it turns to be Milky/Cloudy.
2. H2 Hydrogen --> insert LIGHT splint 'pop' sound is heard.
3. O2 Oxygen --> insert GLOWING splint the splint reglows.
4. NH3 Ammonia --> insert Red litmus paper it turns colour into Blue.
5. Cl2 Chlorine --> Insert litmus paper (any colour) it BLEACHES.
Hope that gives you the information you need and answers you questions!!
Good Luck!

Thanks!

 

[hEbBoOo]

Thanks!

My Pleasure! Also there is a completion!
By also adding on each Ammonia NH3 on the Metals:
1. Fe (II) Iron --> gives Dirty green precipitate that doesn't dissolve in excess.
2. Fe (III) Iron --> gives Red/Brown precipitate that doesn't dissolve in excess.
3. Ca Calcium --> gives White precipitate that doesn't dissolve in excess.
4. Cu Copper --> gives Blue precipitate that forms a DARK Blue SOLUTION.
5. Al Aluminium --> gives White precipitate that DOESN'T dissolve in excess.
6. Zn Zinc --> gives White precipitate that DOES dissolve in excess. Good Luck!! Be Careful! if you needed anything just ask!

 

[MariamHASAN]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_s11_qp_62.pdf

I HAVE THE PROBLEM WITH THE LAST QUESTION OF THE CHEMISTRY 2011 PAPER 6 PLEASE HELP

 

[hEbBoOo]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_s11_qp_62.pdf

I HAVE THE PROBLEM WITH THE LAST QUESTION OF THE CHEMISTRY 2011 PAPER 6 PLEASE HELP

WHICH ONE?!! PLEASE BE SPECIFIC!!!!

 

[MariamHASAN]

QUESTION NUMBER 6

 

[hEbBoOo]

QUESTION NUMBER 6

Which session?!!

 

[Jaxine]

My Pleasure! Also there is a completion!
By also adding on each Ammonia NH3 on the Metals:
1. Fe (II) Iron --> gives Dirty green precipitate that doesn't dissolve in excess.
2. Fe (III) Iron --> gives Red/Brown precipitate that doesn't dissolve in excess.
3. Ca Calcium --> gives White precipitate that doesn't dissolve in excess.
4. Cu Copper --> gives Blue precipitate that forms a DARK Blue SOLUTION.
5. Al Aluminium --> gives White precipitate that DOESN'T dissolve in excess.
6. Zn Zinc --> gives White precipitate that DOES dissolve in excess. Good Luck!! Be Careful! if you needed anything just ask!

Sometimes, they ask for colour of liquid like potassium or carbon etc.. any idea?
And what is pungent gas?
Oh gosh I'm panicking.

 

[kunwar Singh]

Thanks!

fe 2+ dissolves in ammonia

 

[Jaxine]

fe 2+ dissolves in ammonia

I don't think so :\
Fe 2+ and Fe 3+ are insoluble in excess, both in Ammonia and Sodium hydroxide.

 

[thats_me]

Sometimes, they ask for colour of liquid like potassium or carbon etc.. any idea?
And what is pungent gas?
Oh gosh I'm panicking.

the pungent gas is ammonia n carbon powder is black but liquid.. where is it asked?
n potassium they ask for potassium dichromate ?(k2Cr2O4) this is orange yellow