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# The Super Juicy CURRENT YEAR 11 (2012-13) THREAD Mark VI Watch

1. screw English lit.
2. (Original post by Bude8)
screw English lit.
IKR!
(Original post by Bude8)
That takeaway
What was it?
3. (Original post by Bluffroom)
IKR!

What was it?
Mixed Meat & Chips
4. (Original post by Bude8)
screw English lit.
Only bads would say such a thing
5. (Original post by Elm Tree)
Only bads would say such a thing
6. will somebody give me a step by step answer to this question

15cm3 of ethanoic acid was neutralised by 45cm3 of NaOH of concentrration 0.2 molesdm-3

calculate the concentration of the ethanoic acid in grams per decimetre?

i can do it when it just says moles per deimetre but the last step from the CGP book baffles me -_-
7. (Original post by techno836)
will somebody give me a step by step answer to this question

15cm3 of ethanoic acid was neutralised by 45cm3 of NaOH of concentrration 0.2 molesdm-3

calculate the concentration of the ethanoic acid in grams per decimetre?

i can do it when it just says moles per deimetre but the last step from the CGP book baffles me -_-
Devide all the volumes in cm3 by 1000 to get them in dm3

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8. (Original post by techno836)
will somebody give me a step by step answer to this question

15cm3 of ethanoic acid was neutralised by 45cm3 of NaOH of concentrration 0.2 molesdm-3

calculate the concentration of the ethanoic acid in grams per decimetre?

i can do it when it just says moles per deimetre but the last step from the CGP book baffles me -_-
Concentration = Number of Moles / Volume

So how many moles of NaOH?

Write out the balanced equation.

How many moles of NaOH for Ethanoic Acid?

Whatever it is scale the moles up.

Concentration = Number of Moles / Volume

Find the concentration.

Then

Mass in g = moles x Mr

= mass in g/dm^3
9. (Original post by L'Evil Fish)
Concentration = Number of Moles / Volume

So how many moles of NaOH?

Write out the balanced equation.

How many moles of NaOH for Ethanoic Acid?

Whatever it is scale the moles up.

Concentration = Number of Moles / Volume

Find the concentration.

Then

Mass in g = moles x Mr

= mass in g/dm^3
I got 24296 g/dm3 and that really doesnt seem right?
Wait a sec i think I know where i went wrong...
10. (Original post by sammann123)
I got 24296 g/dm3 and that really doesnt seem right?
Wait a sec i think I know where i went wrong...
Probably didn't divide by the 1000
11. (Original post by L'Evil Fish)
Concentration = Number of Moles / Volume

So how many moles of NaOH?

Write out the balanced equation.

How many moles of NaOH for Ethanoic Acid?

Whatever it is scale the moles up.

Concentration = Number of Moles / Volume

Find the concentration.

Then

Mass in g = moles x Mr

= mass in g/dm^3
This stuff was the only part of Chemistry I was actually good at
12. (Original post by justinawe)
This stuff was the only part of Chemistry I was actually good at
It's actually my worst bit atm
13. (Original post by L'Evil Fish)
Probably didn't divide by the 1000
nope, made a stupid mistake in working out the no. mols
14. (Original post by L'Evil Fish)
Concentration = Number of Moles / Volume

So how many moles of NaOH?

Write out the balanced equation.

How many moles of NaOH for Ethanoic Acid?

Whatever it is scale the moles up.

Concentration = Number of Moles / Volume

Find the concentration.

Then

Mass in g = moles x Mr

= mass in g/dm^3

36g ?

0.045 x 0.2 = 0.009 Moles
0.009 /0.015 = 0.6 molesdm-3
(12+3+12+18+18+1) = 60
so i then do mass per decimeter = 0.6 x 60 = 36g per deciimetre ?
15. (Original post by L'Evil Fish)
Probably didn't divide by the 1000
36 g/dm3 sounds like a much better answer
16. (Original post by techno836)
36g ?

0.045 x 0.2 = 0.009 Moles
0.009 /0.015 = 0.6 molesdm-3
(12+3+12+18+18+1) = 60
so i then do mass per decimeter = 0.6 x 60 = 36g per deciimetre ?
yeah thats what i just got
17. (Original post by sammann123)
nope, made a stupid mistake in working out the no. mols
(Original post by techno836)
36g ?

0.045 x 0.2 = 0.009 Moles
0.009 /0.015 = 0.6 molesdm-3
(12+3+12+18+18+1) = 60
so i then do mass per decimeter = 0.6 x 60 = 36g per deciimetre ?
(Original post by sammann123)
36 g/dm3 sounds like a much better answer
I myself don't know the answer

I just gave you general steps and hoped it'd work
Sounds right though
18. (Original post by L'Evil Fish)
I myself don't know the answer

I just gave you general steps and hoped it'd work
Sounds right though
Yeah if we both got the same thing and its a round number its most likely right!
19. (Original post by sammann123)
Yeah if we both got the same thing and its a round number its most likely right!
hi btw, don't think we've spoken?
20. (Original post by sammann123)
yeah thats what i just got
right CGP seriously made the grams part look overcomplicated -_-

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