Chemistry prac p34

[Saloon]

Hey guys pls tell me how to tell if a gas is released during ion analysis... Some you can obviously smell and some you can see... But ones like oxygen carbon dioxide and hydrogen.

Any other tips for the prac would be appreciated
Even if its not regarding ion analysis

And anyone have any idea guess what may come in this p34 chem prac on tuesday (october/november) session?

Thanks

 

[ujjwol]

you can go through the gas test given at quantitative analysis note which will be provided in exam and we should mainly focus on calculating concentration of unknown solution through titration and other question will be ion test

 

[Saloon]

Yep me know about that... Will they ever give us limewater and a splint, or will they only give one so its kinda obvious which gas will be produced?... And could anyone provide a link showing how to do titration calculations, i know most of them just want to make sure

 

[jeevy]

can anyone post useful tips for mole calculations,anions,cations,etc, before our practical exam tomorrow?

 

[autumnsakura]

I think its useful to practice all the calculations you did for your practicals again. Get a hang of no of moles and concentration.

Hey guys pls tell me how to tell if a gas is released during ion analysis... Some you can obviously smell and some you can see... But ones like oxygen carbon dioxide and hydrogen.

Any other tips for the prac would be appreciated
Even if its not regarding ion analysis

And anyone have any idea guess what may come in this p34 chem prac on tuesday (october/november) session?

Thanks

Most of the time, there would be effervescence means there's gas. Test with litmus paper. Blue turning red means CO2 or SO2 (acidic gases). Red to blue would be ammonia. The glowing splint part is the biggest headache for me. It often fails me even when it is suppose to reignite

 

[Z.S.M]

How's everyone feeling about tomorrow?

 

[Z.S.M]

Yep me know about that... Will they ever give us limewater and a splint, or will they only give one so its kinda obvious which gas will be produced?... And could anyone provide a link showing how to do titration calculations, i know most of them just want to make sure

There are only a handful of formulae.......
moles=conc. x vol.
moles= given mass/molar mass
molar volume of gas= 24 dm cube
and you should be able to balance equations and use proprtionality accordingly!
That's about it!

 

[sarah.zarrar]

i need some help too. some questions ask us to suggest what roles some of the ions in the solution provided might be playing. and the mark schemes say either catalyst or oxidizing/ reducing agent. how do we know this?

 

[shikha95]

Any clues on what's happening tomorrow?

 

[Varuna0911]

hello, could you help me with this? How do I test the presence of oxygen or hydrogen? i find it really difficult to see the splint igniting or pop a lighted splint

 

[shikha95]

hello, could you help me with this? How do I test the presence of oxygen or hydrogen? i find it really difficult to see the splint igniting or pop a lighted splint

Hydrogen is most likely given off when a metal is present... and I think for colourless gasses we should hold the test tube closed for a few seconds so that the gas accumilates and we can actually test something.. otherwise all the gas goes off..

 

[Z.S.M]

i need some help too. some questions ask us to suggest what roles some of the ions in the solution provided might be playing. and the mark schemes say either catalyst or oxidizing/ reducing agent. how do we know this?

For example, if you test FA1 and conclude that it contains Fe^2+ ions, and then they ask you to test for ions in FA1+FA3. and you conclude that this mixture contains Fe^3+, then FA3 is oxidising agent cz it OXIDISED Fe^2+ to Fe^3+.
And reverse is true for reducing agent.
As for a catalyst, we all know it USUALLY speeds up a reaction. And its conc. at the end of the reaction is unchanged. If the reagent is in excess, then varying the conc. of catalyst does not affect the rate of reaction. Adding it speeds up the reaction.
"Thumbs-up"

 

[kartsahi]

i have my chemistry practical tomorrow i feel its easy plz friends give me some tips about rate of reaction experiments because i never did it and enthalpy tooooo.

 

[shikha95]

i have my chemistry practical tomorrow i feel its easy plz friends give me some tips about rate of reaction experiments because i never did it and enthalpy tooooo.

I haven‘t done enthalpy changes either, but rate of reaction experiments usually involve a timer and a colour change
PS: Some people said there is a stopwatch in the apparatus list :\

 

[Varuna0911]

also for measuring solids will I be told about how much I will have to measure, for example June 2012 p35

 

[EvilAngel Manoshi]

can anyone post useful tips for mole calculations,anions,cations,etc, before our practical exam tomorrow?

yea jeeval we r in the same session...........i'll show u the calculations during the xam ok love?

 

[MindStealth]

Well you're actually supposed to do the burning splint tests related to those gases but you probably won't be able to I'm sure so just read the paper carefully and predict such gases. Besides they won't usually ask you to identify gases like hydrogen and oxygen so just relax about it.
http://www.xtremepapers.com/community/threads/tips-for-chemistry-practicals-p3.11810/#post-158934

 

[awais tariq]

yea jeeval we r in the same session...........i'll show u the calculations during the xam ok love?

wowwwww....n if u both flunked it then lolzz

 

[Z.S.M]

I haven‘t done enthalpy changes either, but rate of reaction experiments usually involve a timer and a colour change
PS: Some people said there is a stopwatch in the apparatus list :\

I too heard there's a stopwatch. *fingers crossed*

 

[jeevy]

yea jeeval we r in the same session...........i'll show u the calculations during the xam ok love?

hehe..sure luv