Author Topic: Chemistry Help HERE ONLY !!  (Read 106180 times)

Offline ig_kid

  • Newbie
  • *
  • Posts: 19
  • Reputation: 0
Re: Chemistry Help HERE ONLY !!
« Reply #540 on: May 30, 2009, 09:21:27 pm »
Can any one make a mnemonic for the reactivity series containing:
K
Na
Ca
Mg
Al
C
Zn
Fe
Pb
H
Cu
Hg
Ag
Pt
Au

If you already know one please tell im having a lot of difficulty remembering this one.

I cant memorize the action of heat on Hydroxides, Nitrates and Carbonates too.

Im not really the mug up type lol
Please help!


Polite - Potassium
Spotted - Sodium
Leopard - Lithium
Can - Calcium
Meet - Magnesium
Affectionate - Aluminium
Zebra - Zinc
Into - Iron
Tender - Tin
Loving - Lead
Care. - Copper
Single - Silver
Girls, - Gold
Please. - Platinum


Anion Reactivity series:
Someone - sulphate
nice - nitrate
cleans - chloride
broken - bromide
items - iodide
only. - Hydroxide

For crude oil fraction:
Please - petroleum gases
never - naptha
kill - kerosene
dolphines - deisel oil
living - lubricating oil
bravely - bitumen


Note: this was copied from user 12345abc
nyways I hope this will help..... ;) :) :)
« Last Edit: May 30, 2009, 09:36:46 pm by ig_kid »

Q80BOY

  • Guest
Re: Chemistry Help HERE ONLY !!
« Reply #541 on: May 30, 2009, 09:25:24 pm »
Quote
HELP REQUIRED EXPERT PEOPLE!

Please solve Question 5 of  Chem P3      May/June 2002.
No guesses please, because we cannot find a relevant markscheme.
Quote
PLEASE ANSWER THE QUESTION ASKED UP, AS IF YOU ARE WRITING MODEL ANSWERS BY CIE.
Thanks

Waiting....

Q5.

(a) In a liquid, the particles are close together, the intermolecular forces will not allow them to move
apart. They can move in the volume of the liquid to take up the shape of the container. In a gas,
the forces are much weaker and the particles can move apart in all directions to fill the container.

(b) (i) Volume and time were the only options, “amount”, although common was not accepted.

     (ii) Carbon dioxide scored highly as the gas that would diffuse the faster but the explanation often
involved “lighter” or “smaller” or “lower mass” rather than density, relative molecular mass or speed
of molecules.

(c) (i) 110cm3
being 2:11 therefore 20:110

(ii) 80 cm

from 2:8 therefore 20:80

(iii) 120 cm

must be 150 –110 + 80

(d) moles of butyne = 1/6

     moles of water = 1/2

     mass of water = 9 g

hope this helps  ;)

Offline ig_kid

  • Newbie
  • *
  • Posts: 19
  • Reputation: 0
Re: Chemistry Help HERE ONLY !!
« Reply #542 on: May 30, 2009, 09:26:45 pm »
Cation reactivity series:
Please-K
sent-Na
cats-Ca
monkeys-Mg
and-Al
zebras-Zn
in-Fe
large-Pb
hired-H
cages.-Cu
Make-Hg
sure-Ag
padlocked.-Pt


Offline emi

  • SF Geek
  • ****
  • Posts: 530
  • Reputation: 2581
  • former member
Re: Chemistry Help HERE ONLY !!
« Reply #543 on: May 30, 2009, 09:31:45 pm »
some one please help !!!

can some one please solve paper3  O/N 2002 Q1 part (iv)  ?  please and state how u did it ?

and also the same year paper 3 Q3 part (f) all parts  and explain how u did it ? please
former member

Offline reishamix

  • SF Geek
  • ****
  • Posts: 345
  • Reputation: 2
Re: Chemistry Help HERE ONLY !!
« Reply #544 on: May 30, 2009, 09:38:42 pm »
Can any one make a mnemonic for the reactivity series containing:
K
Na
Ca
Mg
Al
C
Zn
Fe
Pb
H
Cu
Hg
Ag
Pt
Au

If you already know one please tell im having a lot of difficulty remembering this one.

I cant memorize the action of heat on Hydroxides, Nitrates and Carbonates too.

Im not really the mug up type lol
Please help!

Kaptn Charlie MAZINTL Caught Me Stealing Gold Plates

Offline reishamix

  • SF Geek
  • ****
  • Posts: 345
  • Reputation: 2
Re: Chemistry Help HERE ONLY !!
« Reply #545 on: May 30, 2009, 09:40:52 pm »
some one please help !!!

can some one please solve paper3  O/N 2002 Q1 part (iv)  ?  please and state how u did it ?

and also the same year paper 3 Q3 part (f) all parts  and explain how u did it ? please

dude
question 1)a) only has like 3 parts

Offline Bani

  • SF Immigrant
  • **
  • Posts: 100
  • Reputation: 12
Re: Chemistry Help HERE ONLY !!
« Reply #546 on: May 30, 2009, 09:45:35 pm »
some one please help !!!

can some one please solve paper3  O/N 2002 Q1 part (iv)  ?  please and state how u did it ?

and also the same year paper 3 Q3 part (f) all parts  and explain how u did it ? please

dude
question 1)a) only has like 3 parts

Q1c) has a iv) part. Emi, did you mean 1c)iv)?

Offline Bani

  • SF Immigrant
  • **
  • Posts: 100
  • Reputation: 12
Re: Chemistry Help HERE ONLY !!
« Reply #547 on: May 30, 2009, 09:54:26 pm »
Anyways, if it is Q1c)iv), then herez how to do it:
                    First, remember that the mole ratio remains constant in a reaction (as in, for a 1:1 the no. of moles will be the same and for 1:2 you would twice the moles for the one with ratio 1 to calculate the moles for the one with ratio2 )
                     So, first find out the no.of moles of CuSO4.5H20.   5/250=0.02 moles
                     Then, find the Mr (molecular mass) of the black powder (CuO), which is 80.
                     Finally, using the equation Moles=Mass/Mr, find the mass. SO, multiply Moles (0.02) by Mr (80) which gives you 1.6g.
            I hope this helped. I'll move onto solving ur next question. :)

Offline godfather93

  • SF Senior Citizen
  • *****
  • Posts: 720
  • Reputation: 799
  • Gender: Male
  • Tomorrow is a day that changes everyday
Re: Chemistry Help HERE ONLY !!
« Reply #548 on: May 30, 2009, 10:02:32 pm »
where do u see the 4th part? ???

Offline MaNa

  • SF Overlord
  • *********
  • Posts: 10219
  • Reputation: 15789
  • Gender: Female
  • InV!ncIbl3!!!!!!
Re: Chemistry Help HERE ONLY !!
« Reply #549 on: May 30, 2009, 10:04:59 pm »
Guys if u need chemistry pass papers as in 1993-2003 or something do let me know i got the pass papers from Zara n if u need it ill forward it
All ur dreams are made,when you're changed to a mirror and the razor blade!!!

Offline cactus_360

  • SF Citizen
  • ***
  • Posts: 275
  • Reputation: 61
  • if ......u r a BE........so.....be a.........BEE!!
Re: Chemistry Help HERE ONLY !!
« Reply #550 on: May 30, 2009, 10:07:03 pm »
plz......can i have them manah!!!!
my id:tascorp20@gmail.com
Newtons (pimped) Law: Every BOOK continues to be in a state of rest or uniform motion UNLESS and UNTIL  an External or Internal exams COME!!!!!!!!!!!!

Offline Bani

  • SF Immigrant
  • **
  • Posts: 100
  • Reputation: 12
Re: Chemistry Help HERE ONLY !!
« Reply #551 on: May 30, 2009, 10:09:22 pm »
some one please help !!!

can some one please solve paper3  O/N 2002 Q1 part (iv)  ?  please and state how u did it ?

and also the same year paper 3 Q3 part (f) all parts  and explain how u did it ? please

Ok, for part f), herez how you do it:
  i) No.Of Moles=Mass/Mr, so, 11.5g/23=0.5 moles
  ii) the mole ratio of Na to S is 2:1 So, to calculate the moles for Sulphur, divide the moles for Na, which is 0.5 by 2  =0.25 moles.
  iii)Mass of sulphur reacted=Moles*Mr, which is 0.25 moles *32 (Mr) = 8g
  iv) Mass of unreacted Sulphur would be the total mass of Sulphur used, which is 10g (given in the question) subtract the mass reacted which is 8g(we calculated in part iii. The answer would be 2g
    I hope this helped. Any confusion, please ask. :)

Offline MaNa

  • SF Overlord
  • *********
  • Posts: 10219
  • Reputation: 15789
  • Gender: Female
  • InV!ncIbl3!!!!!!
Re: Chemistry Help HERE ONLY !!
« Reply #552 on: May 30, 2009, 10:10:35 pm »
plz......can i have them manah!!!!
my id:tascorp20@gmail.com
sure cheak ur inbox:)
All ur dreams are made,when you're changed to a mirror and the razor blade!!!

Offline cactus_360

  • SF Citizen
  • ***
  • Posts: 275
  • Reputation: 61
  • if ......u r a BE........so.....be a.........BEE!!
Re: Chemistry Help HERE ONLY !!
« Reply #553 on: May 30, 2009, 10:20:06 pm »
thanx     u sent me 3 times!!!!!!!!!!!!!!!!coooooooooooool
Newtons (pimped) Law: Every BOOK continues to be in a state of rest or uniform motion UNLESS and UNTIL  an External or Internal exams COME!!!!!!!!!!!!

Offline Naruto

  • SF Citizen
  • ***
  • Posts: 203
  • Reputation: 19
Re: Chemistry Help HERE ONLY !!
« Reply #554 on: May 30, 2009, 10:24:59 pm »
@ Q8BOY
well the answer of the Jun 2002 Q5 (d) the mass of water formed is 27g that what i m getting, becoz the ratio was 1 : 3... so plzz do explain that how you got 9g...