[The_New_Guy]

(Original post by Babyblue)
hey!! do we need to write lengthy experiments in 3b 2008 spec?

and, do we need to know displacement reactions of metals?

In all the past papers,I found no question asked to describe fully how an experiment is carried out.I think,we don't need to write lengthy experiments.
However,knowing about about the displacement reaction of metals could be worthy, as far the specification, issue 4,(1.3.k).

[Grim Rinazyte]

What precipitate color does a ketone form when testing it with benedict's or fehling's solutions ??

[Babyblue]

(Original post by Grim Rinazyte)
What precipitate color does a ketone form when testing it with benedict's or fehling's solutions ??

no ppt

[Grim Rinazyte]

When calculating the energy transferred when a fuel burns using the equation E = m x c x change in T, is m the mass of water or the mass of fluid burnt ??

[Grim Rinazyte]

And guys what are the test results for sulfates, sulfites and carbonates using barium chloride solution ?

[Grim Rinazyte]

can anyone answer me please ?

[Lightuponlight]

(Original post by Grim Rinazyte)
And guys what are the test results for sulfates, sulfites and carbonates using barium chloride solution ?

Test for Sulfate:
Add dilute Hcl followed by Barium Chloride (Bacl2)
Result/observation: White ppt of Baso4 forms, n remains in excess Hcl

Test for Sulfite:
Add Dilute H2S04 and warm! - SO2 gas will b given off.
Observation: Potassium dichromate (IV) color changes from orange to green

Test for Carbonate:
Add dilute H2SO4, CO2 formed, Pass thru limewater!
Obs: Limewater turns milky!

Thats all i know,
not sure if u meant to ask how sulfite n carbonate is tested using BaCl2?
thts smthing new to me ;P

[Ataraxian-Walker]

(Original post by Grim Rinazyte)
And guys what are the test results for sulfates, sulfites and carbonates using barium chloride solution ?

Test for Sulfates:

• Add Barium Chloride Solution acidified with dilute HCl
• Results: White precipitate of barium sulphate forms which is insoluble in HCl
• No effervescence

Test for Sulfites

• Add Barium Chloride Solution acidified with dilute HCl
• Results: White precipitate of barium chloride forms which is soluble in HCl
• No effervescence or test using acidified potassium dichromate paper

Test for Carbonates

• Add Barium Chloride Solution acidified with dilute HCl
• Results: White precipitate of barium chloride forms which is soluble in HCl
• Test gas evolved with limewater. Limewater goes from colourless to milky

Hope this helps.

[Babyblue]

soooooooooooooo. how the hell do you revise for this paper?

[Grim Rinazyte]

Oh ok i get it now thanks a lot.
You simply learn the tests and all that stuff mentioned and keep practising lots of past papers and you will succeed

[Ataraxian-Walker]

How to analyze cations and anions.

[Grim Rinazyte]

When calculating the energy transferred when a fuel burns using the equation E = m x c x change in T, is m the mass of water or the mass of fluid burnt ?? Can you guys answer this question please ?

[Ataraxian-Walker]

(Original post by Grim Rinazyte)
When calculating the energy transferred when a fuel burns using the equation E = m x c x change in T, is m the mass of water or the mass of fluid burnt ?? Can you guys answer this question please ?

Isn't it the mass of the substance?

[Deathliga]

What is the format like for the elimination process?

[MarshmallowBob]

Dear good god the exam is tomorrowwww! D:

[King_Arthur]

(Original post by Grim Rinazyte)
When calculating the energy transferred when a fuel burns using the equation E = m x c x change in T, is m the mass of water or the mass of fluid burnt ?? Can you guys answer this question please ?

for E=MC change in T the mass is the mass of whatever your measuring the temp increase not the mass of the fuel burnt

[Grim Rinazyte]

Ya but what substance, i mean is it the mass of water or the mass of the fuel

[ro0ro0]

(Original post by Grim Rinazyte)
Ya but what substance, i mean is it the mass of water or the mass of the fuel

mass of water

[Grim Rinazyte]

oh right ! i understand now thanks

[ro0ro0]

(Original post by Ataraxian-Walker)
Test for Sulfates:

• Add Barium Chloride Solution acidified with dilute HCl
• Results: White precipitate of barium sulphate forms which is insoluble in HCl
• No effervescence

Test for Sulfites

• Add Barium Chloride Solution acidified with dilute HCl
• Results: White precipitate of barium sulphate forms which is soluble in HCl
• No effervescence

Test for Carbonates

• Add Barium Chloride Solution acidified with dilute HCl
• Results: White precipitate of barium sulphate forms which is soluble in HCl
• Test gas evolved with limewater. Limewater goes from colourless to milky

Hope this helps.

how come you add baruim chloride to carbonates and get baruim sulphate ?? i think you mean baruim carbonate ?