Hello I am the Chemistry Subject Guide. I am gradually adding resources for A2, AS and GCSE Chemistry. I am plodding through the specifications bit by bit but if there is something you want me to address more quickly or if there is a specific question you want advice about, please contact me here. I aim to visit the site at least every other day.
Although there may be other chemistry sites available, this one is special because it puts you in touch with someone who can help you to answer specific questions.
By the way, good luck with forthcoming exams!
I'm not sure that i have any forthcoming tests/exams coming up soon. My exam board is OCR A!
But i was just wondering if you could explain to me using questions and solutions on Balancing equations eg. ionic equations and so forth!
Thank you that would be a great help for me at the moment :)
OK Here are a few to start with. I will set up a page on the main part of the site later on with a few more questions (and the answers). I will reply to this again when I have done it and will include the address.
It will be difficult for youto write your answers on the website so jus do them on paper and check back later.
If these are too easy or too hard, let me know.
Let's go then!
(sorry, equations have to go over three lines)
Give the balanced chemical equation for
magnesium + oxygen
copper oxide + nitric acid
copper nitrate + water
sodium hydroxide + sulfuric acid
sodium sulfate + water
This page is already available throught revisionworld. Have a look at it and see if it helps. If it doesn't, try to explain which bit of it you can't understand.
Hi. I'm doing AQA Chemistry module 3 and i need some help with titration calculations upto higher tier. Thanks.
The basic plan with titration calculations is to get it clear in your head that the number of moles of acid has to match the number of moles of alkali. If you do a titration experiment, that is exactly what you do....you add enough acid until the alkali is just used up and the indicator changes colour (or you could do it the other way round).
Let's assume that you have a known volume (let's say 30 ml) of a standard solution of sodium hydroxide (concentration 0.1 mole per litre).
You want to find the concentration of some hydrochloric acid. You know that you need 17 ml of acid to just neutralise the alkali.
Are you happy to calculate the number of moles of sodium hydroxide in a certain volume of a certain concentration? As an example, could you find the number of moles of sodium hydroxide if you have 30 ml of a solution containing 0.1 mole per litre?
If you know how many moles of alkali (30 x 0.1 /1000), then there must be exactly the same number of moles of acid in the 17 ml.
The 30 x 0.1 / 1000 moles of acid that you need are all contained in the 17 ml. So you can say that 1 ml of the acid must contain (30 x 0.1 / 1000) / 17 moles of acid.
1000 ml (1 litre) contains 1000 times this amount....which is 30 x 0.1 / 17.
Some people like to use a "magic formula"..something like M1V1 = M2V2. This can work for simple reactions but can be difficult to use for more complicated ones.
See if what I have said has helped and get back online to either tell me that you are OK or that you need more help. It might be a good idea to start a new thread for this conversation so that it keeps things organised.
Hope this helps.
anyone wants to help me feel free, not enought sources here
Please let me know what level you are at (GCSE / AS etc) and I will try to help.
It would be easier if you start a new thread so that anyone else wanting help on this can see it.
Try to state which bits you can't do.
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