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I want a easy formula for integration A2
https://www.khanacademy.org/math/integral-calculus/indefinite-definite-integrals/integration_by_parts/v/deriving-integration-by-parts-formula -
Chemistry: Post your doubts here!
They'll accept any appropriate representation of the structure (structural, displayed, skeletal) as long as it is right. This has to do with optical isomerism. As you can see it has two chiral centress, so you'll have rotate them around, and see which matches with F. It's impossible to explain... -
Chemistry: Post your doubts here!
We need to look at the bonding in the -CONH2 group. Like any other double bond, a carbon-oxygen double bond is made up of two different parts. One electron pair is found on the line between the two nuclei - this is known as a sigma bond. The other electron pair is found above and below the... -
Chemistry: Post your doubts here!
It feels contradictory to me as well, but this is what makes sense to me: Fluorine has the lowest polarizability of all atoms. From this statement, we can say that the C-F bond isn't polarized enough to form the strong hydrogen bonds i.e. the δ- of the F isn't negative enough to form a strong... -
Chemistry: Post your doubts here!
Flourocarbons are hydrophobic. http://en.wikipedia.org/wiki/Fluorine "Also, adding fluorine to organics increases their lipophilicity (ability to dissolve in fats) because the carbon–fluorine bond is even more hydrophobic than the carbon–hydrogen bond."... -
Chemistry: Post your doubts here!
In order for a halogenoalkane to dissolve in water you have to break attractions between the halogenoalkane molecules (van der Waals dispersion and dipole-dipole interactions) and break the hydrogen bonds between water molecules. Both of these cost energy. Energy is released when new attractions... -
A LEVEL CHEMISTRY APPLICATION REVISION NOTES
Yeah Mash'Allah. :) Well, you should practice the past papers as much as possible. Clear out any doubts with your tutor. Good luck! -
A LEVEL CHEMISTRY APPLICATION REVISION NOTES
Averaging around 82-85. :) -
Chemistry: Post your doubts here!
This page does a great job in thoroughly explaining it http://www.chemguide.co.uk/physical/acidbaseeqia/phcurves.html Make sure you understand acid-base reactions, pH calculations, and buffer solutions first though. -
Chemistry: Post your doubts here!
Cyclohexane is an unsaturated organic compound so it wouldn't react with NaOH. Phenol does react with NaOH, as phenol is acidic (lone pair of O being delocalised into the ring causes the O-H bond to be more polar so the H breaks off more easily) -
Chemistry: Post your doubts here!
Have you read the chapter on partition coefficients? This page does a great job in explaining the concept and how to do the calculations. http://www.chemguide.co.uk/CIE/section112/learningf.html Read that page and try to figure out how to solve the question yourself. It's mostly math anyway... -
Chemistry: Post your doubts here!
Pick a point on one of the graphs Draw a tangent line and calculate the gradient of that line. This is the rate. Take the appropriate concentrations and place the values of the rate and concentrations in the rate equation Solve for k. -
A2 Chemistry notes help
You'll need Microsoft Office 2007 or later to open the docx files. -
A2 Chemistry notes help
Notes for section B, although they aren't "short" lol. -
Chemistry Help!
Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons. It is one of the key concepts in chemistry, and so you should spend some time making sure that you fully understand it - what it means, what causes electronegativity differences, and what effects it... -
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A LEVEL CHEMISTRY APPLICATION REVISION NOTES
It took me two nights. Besides, section A is worth a lot more than section B. I'd focus on getting 60 or 65 out of 70 in section A, and something like a 15 in section B is good enough to secure an A. :) -
Chemistry: Post your doubts here!
Teachers usually treat the mark scheme as the Bible or something lol. No need to draw it exactly as the mark scheme. Just make sure your diagram includes the relevant points quoted in the mark scheme, as those are what was marked : power supply electrolyte + filter paper buffer acid mixture...