i am finding this chemistry very very hard ( as level ) can someone help me with a Q Watch

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Hunny123
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i dont think chem is for me to be honest but here we go
two questions:

how do you find chemistry? how are you good at it?
can you give me any tips? revision guides?

here is the question

When Chlorine reacts with trichloromethan, tetrachloromethan, CCL4 is formed

write a 1) The overall equation for this reaction

2)state one essential condition for this reaction

The mechanism for the chlorination of trichloromethan is free-radical substitution, which proceeds by a series of steps. Write equations for the steps named below in this Clorination:

initiation step

first propagation step

second propagation step

a termination step

A chloroalkane, W was shown to contain 37.2 % carbon and 55 % chlorine by mass. The remainder of the compound was Hyrdrogen. Calculate the empirical formula of compound W

part 2 what additional info would be needed to calculate the molecular formula of compound W
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_ELiTeCaRR_
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1a) CHCl3 + Cl2 -> CCl4 + HCl

b) condition: sunlight

initiation step: Cl2 -> 2Cl

first prop: CHCl3 +Cl => CCl3 +HCl

second prop:

CCl3 +Cl2 => CCl4 +Cl

term:
2 CCl3 =>C2 Cl6

and the calculation:
% of the mass = 7.8 %
molC = 55/ 33.5

so the ratio is 1.55

sorry i'm too tired to do that

and the last part:

you will need the relative molecular mass
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_ELiTeCaRR_
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any tips? don't buy any of that bs revision stuff unless you're an E grade candidate and you need all the exam technique you can get

i like chemistry, therefore i enjoy it and do well in it- just practice on the equations and learn all the facts


cobra is also one to listen to - he's very good =D
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Hunny123
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(Original post by _ELiTeCaRR_)
any tips? don't buy any of that bs revision stuff unless you're an E grade candidate and you need all the exam technique you can get

i like chemistry, therefore i enjoy it and do well in it- just practice on the equations and learn all the facts


cobra is also one to listen to - he's very good =D
thank you so very much _ELiTeCaRR_
really appreciated your help
thank you
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_ELiTeCaRR_
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(Original post by Hunny123)
thank you so very much _ELiTeCaRR_
really appreciated your help
thank you
you're welcome
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ShOcKzZ
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is this the dazya?
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_ELiTeCaRR_
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(Original post by ShOcKzZ)
is this the dazya?
it is.
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hornblower
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(Original post by Hunny123)
A chloroalkane, W was shown to contain 37.2 % carbon and 55 % chlorine by mass. The remainder of the compound was Hyrdrogen. Calculate the empirical formula of compound W

part 2 what additional info would be needed to calculate the molecular formula of compound W
Percentages divided by r.a.m.:

C: 37.2 / 12 = 3.1

Cl: 55 / 35.5 = 1.549...

H: 7.8 / 1 = 7.8

Dividing by smallest:

C: 3.1 / 1.549... = 2.001...

Cl: 1.549... / 1.549... = 1

H: 7.8 / 1.549... = 5.035...

Therefore ratio of C:Cl is 2:1:5, and empirical formula is C2H5Cl.

To find the molecular formula of the compound, you need its relative formula mass.
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_ELiTeCaRR_
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(Original post by hornblower)
Percentages divided by r.a.m.:

C: 37.2 / 12 = 3.1

Cl: 55 / 35.5 = 1.549...

H: 7.8 / 1 = 7.8

Dividing by smallest:

C: 3.1 / 1.549... = 2.001...

Cl: 1.549... / 1.549... = 1

H: 7.8 / 1.549... = 5.035...

Therefore ratio of C:Cl is 2:1:5, and empirical formula is C2H5Cl.

To find the molecular formula of the compound, you need its relative formula mass.

Team Work
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ShOcKzZ
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(Original post by _ELiTeCaRR_)
Team Work
where are u gng nxt yr then?
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_ELiTeCaRR_
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(Original post by ShOcKzZ)
where are u gng nxt yr then?
manchester or liverpool
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ShOcKzZ
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(Original post by _ELiTeCaRR_)
manchester or liverpool
manchester is better
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_ELiTeCaRR_
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(Original post by ShOcKzZ)
manchester is better
omg no ****ing ****,
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username9816
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(Original post by _ELiTeCaRR_)
manchester or liverpool
Go to Manchester.
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ShOcKzZ
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(Original post by _ELiTeCaRR_)
omg no ****ing ****,
why the "or" then? dumbass.
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_ELiTeCaRR_
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(Original post by ShOcKzZ)
why the "or" then? dumbass.
because LIVERPOOL is my 1st choice for dentistry cuz i fell in love w/ the place and manch my insurance ( you never know what might happen )
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Ralfskini
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(Original post by _ELiTeCaRR_)
omg no ****ing ****,

What are you like?

:rolleyes:

(it's a rhetorical question by the way)
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_ELiTeCaRR_
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(Original post by bono)
Go to Manchester.
it'll be a toughy
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_ELiTeCaRR_
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(Original post by Ralfskini)
What are you like?

:rolleyes:

(it's a rhetorical question by the way)
lol duh!
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_ELiTeCaRR_
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(Original post by Ralfskini)
What are you like?

:rolleyes:

(it's a rhetorical question by the way)
where in essex are you?
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