Edexcel (IAL) Unit 2 Chemistry June 10th

hello
any useful links to study ?


I need a study plan please

Hey, http://www.chemguide.co.uk is a good website it has alot of resources... I guess your main study plan should be to do past papers and learn from your mistakes, that's what I'm doing anyways

CGP is the number one life saver for anyone!! Like seriously if you don't have it go borrow it, buy it whatever it takes just to read the CGP book (for Edexcel). It includes everything you need to know for the exam and especially helps for last minute revision.

what is the cgp ?
the blue book or the pink or what??

do you think nucleophilic substitution of ammonia is an important topic?

This is the exact appearance of the book.

Yes it is and can be asked this time because the always ask the alcoholic and aqueous KOH qquestion..

Where can I get this from? For free?

The ion that gives a bleaching property is ClO- or OCl- ? Or are they the same?

Technically they should be the same because the charge applies to the whole compound and not individual atoms. However it is much more preferable and accurate to write it as ClO- because apparently the current chemical formula naming system is according to the alphabetical order of elements. It is called the 'Hill' system for your further information and interest.

Heyy guys, so i seriously am confused about something. Okay so the thermal stability of group two carbonates and nitrates increases down the group making it more difficult to decompose. I am unsure of the reason for this... It is because

A) at top of group the ions are smaller will a larger charge ( large charge density) and therefore result in a stronger force of attraction between the metal ion and the O2 minus of the carbonate ion thus the energy released when those two come together is great and very exothermic. And it states that for a chemical reaction to occur the erergy released when bonds are formed( when O2 minus amd metal ion meet ) must be greater then the energy required to break bonds. Therefore as a smaller metal ions is more exothermic when it meets a O2minus ion ,less additional energy is required for the reaction to take place at top of group but as you go down more additional energy is required as the reaction is less exothermic.

Or is the reason

B) a smaller metal ion at the top of the group with a large charge density has a greater polarising effect on the carbonate ions electrons thus making the bond weaker and easier to break and hence less engery required at top of group and more at bottom ???

I seriously need help becasue the text book pushes more for the first answer but my teacher for the other ....???? 😱😱😱

As you go down the group thermal stability increases because the size of the cation increases and the nuclear charge decreases and a result the charge density decreases. This means that the polarizing power decreases down the group with decrease in charge density. As a result the ability of the cation to distort the anion is weak as a result we say that the compunds become more ionic down the group. As a result compounds are more stable thus a large about of energy needs to be supplied to decompose the carbonate or nitrate.