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Do not get titrations at all, please help!!

So I have my GCSE exam tomorrow, I don't understand it at all :frown: The process is simple & everything, but this is my main problems:

1)If you use them to work out the concentration, don't you have to know how much acid would normally neutralise an alkali anyway? How would you find that out? Is it standard - equal number of atoms? (btw our course doesn't cover moles, only RFM)
2)Titration seems completely pointless, if you want to work out concentration why not use distillation?
3)The calculations have about 10 steps, which I don't get - for example why do you divide by 1000?

Please help or I'm actually going to fail, don't know anything else, don't even know why I'm taking it for A level :frown:
Marsha2112
So I have my GCSE exam tomorrow, I don't understand it at all :frown: The process is simple & everything, but this is my main problems:

1)If you use them to work out the concentration, don't you have to know how much acid would normally neutralise an alkali anyway? How would you find that out? Is it standard - equal number of atoms? (btw our course doesn't cover moles, only RFM)
2)Titration seems completely pointless, if you want to work out concentration why not use distillation?
3)The calculations have about 10 steps, which I don't get - for example why do you divide by 1000?

Please help or I'm actually going to fail, don't know anything else, don't even know why I'm taking it for A level :frown:



woah...didnt have do anything like this when I did GCSE.

1) You use them to work out the VOLUME (im dm3) of acid required to neutralise x amount of base (or vice versa)
2) Again, your not trying to work out concentration, you want volume. (mol dm^3 = Concentration / cm^3 or dm^3 = Volume)
3) You are given units in CM^3, you need them in DM^3 , (1 cm^3 is equal to 0.001dm^3) so you divide by 1000.

Just remember the formula:

Moles = Concentration x Volume

so Volume = Moles / Concentration
Reply 2
Avatar for Lrilol
Lrilol
1
Concentration = Moles / Volume
Moles = Concentration * Volume
Moles = Mass / Mr

All you need to know :biggrin:
Reply 3
Avatar for Marsha2112
Marsha2112
OP
15
Erm guys, first of all there are no MOLES in the course! I don't even know what they are!
Second, we do use them to find an unknown concentration, all the questions are trying to find an unknown concentration.
But thanks anyway
(I totally failed the paper though, made up some comedy for half of it, that's yet another predicted A* down the drain :p:)
Reply 4
Avatar for dude55
dude55
10
Marsha2112
Erm guys, first of all there are no MOLES in the course! I don't even know what they are!
Second, we do use them to find an unknown concentration, all the questions are trying to find an unknown concentration.
But thanks anyway
(I totally failed the paper though, made up some comedy for half of it, that's yet another predicted A* down the drain :p:)


Depends what course you're doing, im doing edexcel and we do loads of work on Moles. By the way the mole is just unit used by chemists to make calculations easier. it is equal to the formula mass of a compound or element in grams, e.g. one mole of iron is 56g. Also moles contain what is called the avagadro constants which is 6*10^23 particles. all moles no matter what substance contain the avagadro constant
Reply 5
Avatar for Marsha2112
Marsha2112
OP
15
dude55
Depends what course you're doing, im doing edexcel and we do loads of work on Moles. By the way the mole is just unit used by chemists to make calculations easier. it is equal to the formula mass of a compound or element in grams, e.g. one mole of iron is 56g. Also moles contain what is called the avagadro constants which is 6*10^23 particles. all moles no matter what substance contain the avagadro constant


Oh ok, thanks :smile:
We do OCR 21st Century Science, the dossiest course by far! And written by morons, there's a picture in the Physics textbook of a woman microwaving sushi :lolwut:

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