Read the post below before you read this one.

Ok, Iv'e managed to get a picture up. Basically, the two on the top right show the ring (like my book said), and then the other two show double bonds where the electrons would go instead (which is what my book specifically said wouldn't happen). So does any one have any ideas?


Also, do we need to know anything on halogenoalkanes?

Benzene is weird

I have been revising Benzene, as you do, and I have discovered a problem. I need someone to explain to me, and am I right or confused?

Firstly, Benzene is a ring of 6 carbons with a hydrogen on each carbon.
Secondly, each carbon has 4 outer electrons. Therefore, one of these will bond with its hydrogen, one with the carbon to its left, and another electron to the carbon on its right. This should mean there is one electron left over.

I read up on it and it said that the extra electrons from each carbon are spread out evenly and are shared by all 6 carbon atoms in the ring... ok, so when you see the skeletal form of benzene the ring in the middle are these "extra" electrons? This is electron delocalisation.

That part I got, untill i started looking for pictures on google for benzene. My book originally explained that the "extra" electrons form the ring, and do NOT make three double bonds between the carbons instead. But, on google there where pictures of the skeletal formula (with the ring) AND 3D models that had three double bonds (rather than a ring).

If you go onto google and search benzene you will understand, but now I'm confused to which is correct. I presume they both are but I don't understand how? Surely it's one or the other?

Please help me, anyone :-(

OOOOOOOOOOOHHHHHHHH

Look what I found....

I dno if its good or not...

http://www.btinternet.com/~melee3d/revision/chemistry/alcohols.html

AAAAAAAAAAHHHHHHHHHHHHHHHHHH

OMG somebody please help me lord! I cannot find any time to do revision because of work and my damn family! I am panicking! I have three subjects to revise for and I have no time... and when I do have time I don't know where to start! I really want to do well but I just don't know how! I have never been soo worried I just feel like what I am doing isn't enough since I am just reading and writing notes! Does anybody please have any suggestions? Does anyone want to tell my boss I can't work because of my revision? I am too scared, maybe if one of you teachers called and sounded all important? ...yes?...no?....

More revision resources

I have uploaded more revision resources today, for the Year 12 and 13 units as follows:

Year 13 - Unit 2849:
Resources to consolidate learning on order of reaction and equilibrium constants.

Year 12 (and Year 13 retake) - Unit 2850:
Resources to help you revise enthalpy changes, plus some on entropy and volume of gases which we have been doing very recently in lessons.

All of the resources can be found by clicking on the relevant unit under 'Revision resources' and then right-clicking on the link to a particular resource, doing 'Save Target As' and then opening it. Please let me know if you are having trouble accessing any of the worksheets and I will email them to you as attachments.

Todays practical!

Does anyone have the results for the enthalpy change of sodium carbonate?
Our group tested sodium hydrogencarbonate and the enthalpy change was + 46.95 kj/mol

Thanks!

Extra Revision Sessions!

Please make use of all the revision resources that are now available for downloading through the 'Revision Resources' links. If you are having trouble downloading them, I would suggest right-clicking on the name of the resource and then doing 'Save Target As' or trying to do it from a different computer!

By the way, I have today uploaded lots of revision resources for retake Unit 2848.

I would like to start revision sessions for both the Year 12 and 13 modules this week, as follows:

Year 13 revision for A2 Unit 2849
Friday, 14th December (Lesson 2) - What's in a Medicine?

Friday, 21st December (Lesson 1) - Designer Polymers

Friday, 11th January (Lesson 2) - Engineering Proteins

Friday, 18th January (Lesson 1) - The Steel Story

Year 12 and 13 revision for AS Unit 2850
Monday, 17th December (lunchtime) - Trends in physical properties

Wednesday, 19th December (lunchtime) - Calculations

Monday, 7th January (lunchtime) - Enthalpy changes and Hess' Law

Wednesday, 9th January (lunchtime) - Radioactivity, absorption and emission spectra

Wednesday, 9th January (3.30 - 4.30pm) - Last minute revision!

PLEASE FEEL FREE TO BRING YOUR LUNCH TO THESE SESSIONS!!

Year 13 revision for retake AS unit 2848
Please see Mrs Sudbery ASAP about arranging extra revision sessions for this retake unit.

I look forward to seeing you all at this week's revision sessions! Please see me if you are not able to attend for any reason.

Year 12 mock exam

We have decided to hold your mock exam (on the whole of Unit 2850) on Wednesday, 19th December during our double lesson (Lessons 3 and 4).

Please ensure that you prepare as fully as you can for this exam over the next 2 weeks so that your mock grade is an accurate reflection of your level of understanding.

And if any you Year 13 students who are retaking Unit 2850 are free during these lessons, you are welcome to join us for the mock....!

By the way, just in case there is any confusion because of the late entries, all Year 12 students have been entered to sit the Unit 2850 exam in January and the exact date of the exam is Thursday, 10th January.

Year 13 mock exam?

is our mock exam next thursday [13th]?
if so, you may wish to hurt me as i won't be in the lesson that day
i have a interview/open day at university.
is it possible that you can give me the exam beforehand or i could do it another time?

New resources uploaded

Just to let you know that I have at last added some revision resources for those of you who are retaking Unit 2848 in January - on halogens and working out oxidation states only so far, but I'll keep adding.

Also, for Year 12 students and those of you who are retaking Unit 2850, I have uploaded some questions on describing and explaining the trends in physical properties across Period 3 and down Group 2. Please have a go at these, especially those of you who identified this as being a weaker area in your test on Monday.

ALL OF THE RESOURCES MENTIONED CAN BE FOUND BY CLICKING ON THE RELEVANT UNIT UNDER 'Revision resources' ON THE RIGHTHAND SIDE OF THIS PAGE. (Once you reach the list of available resources on the next page, I would suggest right-clicking on the links and doing 'Save Target As', as this seems to take less time although you may still need to be patient!)

Remember that all of the tick lists and some practice exam papers are available if you follow the relevant links on the blog. Please take advantage of this AND USE THEM - let me know if you're having trouble accessing them in any way and I will print off paper copies for you.

Wooo miss Im logged on

its all good miss ive worked out how to log in!

Work from recent Year 13 lessons

Please remember to check the 'Work from recent lessons', especially if you have missed a lesson, if you have lost any of the worksheets or if you just want a blank copy of any of the worksheets that we have used.

Following on from today's lesson, I have added a worksheet that will enable you to practice using experimental data to work out the order of reaction with respect to each of the reactants.

Past exam papers

I have now uploaded links to past exam papers for AS Units 2850 and 2848 and A2 Unit 2849. Please click on the links in the white box on the righthand side of this page. (You may have to scroll down for a while as there's lots on here now!!)

Don't forget to 'vote' to tell me when would be the best time for extra revision sessions for you!

New resources uploaded

I am currently in the process of uploading more revision resources. So far, I have added materials relating to the following areas of the course:

AS Unit 2850 - Elements of Life:
Mass spectrometry
Shapes of molecules
Trends in physical properties in the Periodic Table

AS Unit 2850 - Developing Fuels:
Hess' Law
Volumes of gases
Structural Isomerism

A2 Unit 2849 - The Steel Story:
Half-equations

Please click on the relevant link under 'Revision resources' (on the righthand side of this blog page) and let me know if you have any difficulties in downloading the materials. I will try to add more materials for the A2 modules and also some for the other retake unit on Monday or Tuesday.

Please take part in the poll (in the green box to the right of this post) to indicate when would be the best time for extra revision sessions for Chemistry and let me know if there are any topics in particular (for any of the 3 modules that are being examined in January) that you would appreciate revision practice on.