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Chemistry question
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Topic: Chemistry question (Read 1060 times)
yasser37
SF Citizen
Posts: 228
Reputation: 2832
Chemistry question
«
on:
May 28, 2010, 12:45:38 pm »
Hi guys
Nov. 02
Q. 4
Part e
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yasser37
SF Citizen
Posts: 228
Reputation: 2832
Re: Chemistry question
«
Reply #1 on:
May 28, 2010, 12:48:30 pm »
also Q.6 Part b ii
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nid404
Guest
Re: Chemistry question
«
Reply #2 on:
May 28, 2010, 04:27:54 pm »
4)e) H2O(l) + CO(NH2)2(aq) ? CO2(aq) + 2NH3(aq)
–287.0 + –320.5 –414.5 –81.0 X 2
Enthalpy of products= -414.5-(81X2)=-576.5kJ
Enthalpy of reactants= -287-320.5=-607.5 kJ
= -576.5kJ- (-607.5)=+31 kJ/mol
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nid404
Guest
Re: Chemistry question
«
Reply #3 on:
May 28, 2010, 04:37:47 pm »
6)b) ii)
C
5
H
11
OH + NaBr------> C
5
H
11
Br+ NaOH
Molar Ratio of C
5
H
11
OH : C
5
H
11
Br is 1:1
Yield is 60%
15g of C
5
H
11
Br = 15/Mr moles Mr of bromopentane=151g
no of moles= 15/151 = 0.1 approx
since yield is 60%
60/100 X no of moles of C
5
H
11
OH = 0.1 moles of C
5
H
11
Br
no of moles of C
5
H
11
OH= 0.166 moles
Mr of C
5
H
11
OH= 88g
Mass of C
5
H
11
OH required= 0.166X 88=14.7 g
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unknown 101
SF Joker
SF Master
Posts: 1660
Reputation: 5946
Gender:
FEELING GREATER THAN EVERR :D
Re: Chemistry question
«
Reply #4 on:
May 28, 2010, 09:11:53 pm »
i wouldve helped you, but she answered faster!!
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moon
SF Citizen
Posts: 222
Reputation: 770
Re: Chemistry question
«
Reply #5 on:
May 29, 2010, 01:25:09 am »
can somebody help me to solve question no. 3 and Q1(c), (d), (e), (f) in ppr 52 Nov. 09.
thanx in advance.
«
Last Edit: May 29, 2010, 01:38:03 am by moon
»
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nid404
Guest
Re: Chemistry question
«
Reply #6 on:
May 29, 2010, 06:43:35 am »
I'm doin AS...so p5 is greek to me
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moon
SF Citizen
Posts: 222
Reputation: 770
Re: Chemistry question
«
Reply #7 on:
May 29, 2010, 09:48:14 am »
ok thanx a lot..
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