Chemistry ATP (Important points for Both IGCSE and O-level)

[Nibz]

One is a physical test and the other is a chemical test!
If they ask for the physical one => Use the 'boiling point' method!
If a chemical test is being asked, then mention one of the two tests I've provided!

 

[TatsuEG]

I am not sure but I think those measure the presence of water , not purity

 

[ayusuf1234]

chemistry sucks i have the exam tomorrow and its 11.30 pm and i dont know anything
i just wanted to share my pain . lol

 

[ayusuf1234]

and btw that is a test for Purity if u want a test for the presence of water then use anhydrous copper sulphate (White-Blue) or cobalt chloride paper.

 

[scarface007]

walikum as salam
thnk u soo much fr dese notes

 

[respect1]

Bromothymol Blue:

Acid (Yellow) , Neutral (Dark green) , Alkaline (Blue)

Are we even supposed to know about this indicator?? It's the first time i am hearing it...Is it in the syllabus?
Thanks

 

[respect1]

And one more thing Nibz, isn't adding a carboxylic acid a test for ethanol?
You get a pleasant smelling substance which is an ester..

 

[xIshtar]

And one more thing Nibz, isn't adding a carboxylic acid a test for ethanol?
You get a pleasant smelling substance which is an ester..

It is one possible test, but a lit splint which burns is also one..

 

[TatsuEG]

Bromothymol Blue:

Acid (Yellow) , Neutral (Dark green) , Alkaline (Blue)

Are we even supposed to know about this indicator?? It's the first time i am hearing it...Is it in the syllabus?
Thanks

It's not recommended in the chemistry syllabus , only Methyl orange and Phenophthanil which is used in Titration


Also Universal Indicator and Litmus paper but don't use those in Titration

 

[JiViFiDi]

why thank u. what goes around, comes around. i was good at bio, and i helped alot of people out, and my weak point is chem. i didnt study squat for the ppr6, and u saved my ass. thanks

 

[himanshu1995]

<Comment Removed>

---You shouldn't discuss the paper before 24 hours!---

 

[XPFMember]

Assalamoalaikum!!

Waalaikumassalam!!

wud like to gie a sugestion...post it as a word doc. as well..with all formatting i mean...it's more easier and better wen u see i wit different kin of colours and formatting and all tat

Anyways thanks a lot! Jazak ALlah Khair!! gud work!

If only I had time!
You can do that, if possible !

I guess it's late now! Paper's over already!

 

[KHuSHaL_KaMaL..007]

Umm, Nibz, nitrogen is not toxic/poisonous. Otherwise, we'll all be dead breathing 78% of nitrogen in air 24/7!

dude, its Nitrogen Dioxide
Justin Bieber was caught smoking weed. In related news, weed just got a lot less cool

 

[Sijal Mirza]

In Fermentation, how can carbondioxide escape if bung is used? :/

 

[Sijal Mirza]

and in oxidising agents part.. (VI) and (VII) what are these?
cant be their oxidation states :/

 

[bubbles1997]

Aoa. Can anyone help me with oxidising agents and reducing agents? I don't understand it....
Please list the names...

 

[Sijal Mirza]

Aoa. Can anyone help me with oxidising agents and reducing agents? I don't understand it....
Please list the names...

the only ones included in our syllabus are mentioned here in comments
https://www.xtremepapers.com/commun...e-and-insoluble-substances.24846/#post-516109

 

[Sijal Mirza]

Aoa. Can anyone help me with oxidising agents and reducing agents? I don't understand it....
Please list the names...

An oxidising agent (also oxidant, oxidizer or oxidiser) is a substance that oxidizes (removes electrons from) another reactant in a redoxchemical reaction. The oxidising agent is reduced by taking electrons onto itself and the reactant is oxidised by having its electrons taken away.

A reducing agent (also called a reductant or reducer) is the element or compound in a reduction-oxidation (redox) reaction that donates an electron to another species; however, since the reducer loses an electron we say it is "oxidized". This means that there must be an "oxidizer"; because if any chemical is an electron donor (reducer), another must be an electron recipient (oxidizer). Thus reducers are "oxidized" by oxidizers and oxidizers are "reduced" by reducers; reducers are by themselves reduced (have more electrons) and oxidizers are by themselves oxidized (have fewer electrons).

P.S. I do not own anything.

 

[Sijal Mirza]

Aoa. Can anyone help me with oxidising agents and reducing agents? I don't understand it....
Please list the names...

Redox reactions, or oxidation-reduction reactions, have a number of similarities to acid-base reactions. Fundamentally, redox reactions are a family of reactions that are concerned with the transfer of electrons between species. Like acid-base reactions, redox reactions are a matched set -- you don't have an oxidation reaction without a reduction reaction happening at the same time. Oxidation refers to the loss of electrons, while reduction refers to the gain of electrons. Each reaction by itself is called a "half-reaction", simply because we need two (2) half-reactions to form a whole reaction.

 

[bubbles1997]

Redox reactions, or oxidation-reduction reactions, have a number of similarities to acid-base reactions. Fundamentally, redox reactions are a family of reactions that are concerned with the transfer of electrons between species. Like acid-base reactions, redox reactions are a matched set -- you don't have an oxidation reaction without a reduction reaction happening at the same time. Oxidation refers to the loss of electrons, while reduction refers to the gain of electrons. Each reaction by itself is called a "half-reaction", simply because we need two (2) half-reactions to form a whole reaction.

Thanks, you've been a great help!