Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 357726 times)

Offline Helium

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2865 on: June 06, 2010, 03:49:17 pm »
Yup thats right  ;D

there anything wrong here..v

2C4H9OH + 11.75O2---->8CO2 + 9.5 H2O


Anyways Thanks A@di, Vin n Kimo :D
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Offline Ivo

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2866 on: June 06, 2010, 03:52:33 pm »
Right, my major(est) doubt so far.  Cropped up in many papers before, but for one example, w02, Q2) c) ii).  I don't understand any of the concentration, temperature stuff and sketching graphs.  Cos everytime they have a different y-axis, and sometimes they say same volume of oxygen level, sometimes it doubles.  Can someone please explain a general rule.

Many thanks in advance; I'm sweating over this!  :o
Always willing to help!  8)
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Offline Lariemeeva

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2867 on: June 06, 2010, 04:03:49 pm »
https://studentforums.biz/index.php/topic,54.msg253414.html#msg253414

Q 7-a (i)
In the MS it's written "an equation that gives: alkene + alkane or alkene + alkene + hydrogen"

Why is that. Cracking of alkanes --> alkene + hydrogen not alkene + alkane

Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2868 on: June 06, 2010, 04:07:18 pm »
https://studentforums.biz/index.php/topic,54.msg253414.html#msg253414

Q 7-a (i)
In the MS it's written "an equation that gives: alkene + alkane or alkene + alkene + hydrogen"

Why is that. Cracking of alkanes --> alkene + hydrogen not alkene + alkane
crackin of alkanes can be also used to produce hydrogen

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Offline Lariemeeva

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2869 on: June 06, 2010, 04:10:20 pm »
^Trust me. I know that very well. That's not my question. Why is it alkene + alkane + hydrogen

Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2870 on: June 06, 2010, 04:10:42 pm »
Yup thats right  ;D

there anything wrong here..v

2C4H9OH + 11.75O2---->8CO2 + 9.5 H2O


Anyways Thanks A@di, Vin n Kimo :D

umm yeah its wrong ..we just did it for u :/
NO secrets to SUCCESS , it is the result of 1.HARD WORK 2.GOOD PREPARATION 3.LEARNING FROM FAILURE
But it ain't how hard you hit; it's about how hard you can get hit, and keep moving forward-Balboa

Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2871 on: June 06, 2010, 04:11:40 pm »
^Trust me. I know that very well. That's not my question. Why is it alkene + alkane + hydrogen
dunno :O
NO secrets to SUCCESS , it is the result of 1.HARD WORK 2.GOOD PREPARATION 3.LEARNING FROM FAILURE
But it ain't how hard you hit; it's about how hard you can get hit, and keep moving forward-Balboa

Offline Helium

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2872 on: June 06, 2010, 04:17:49 pm »
^Trust me. I know that very well. That's not my question. Why is it alkene + alkane + hydrogen

How can that be?

All cracking reactions Give:

1) An Alkane with a shorter chain than the original, and a short chain Alkene

2)or two or more alkenes and hydrogen.


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Offline 2010

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2873 on: June 06, 2010, 04:18:29 pm »
i need help with May/June 2009
Q3b.
i have attached  it..
Please help!!

Offline mdwael

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2874 on: June 06, 2010, 04:20:54 pm »
Can someone draw for me an isomer for pentan-1-ol CH3-CH2-CH2-CH2-CH2-OH
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Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2875 on: June 06, 2010, 04:26:03 pm »
Can someone draw for me an isomer for pentan-1-ol CH3-CH2-CH2-CH2-CH2-OH

PENTAN -2-OL


JUST PUT THE OH on the second CH2 
NO secrets to SUCCESS , it is the result of 1.HARD WORK 2.GOOD PREPARATION 3.LEARNING FROM FAILURE
But it ain't how hard you hit; it's about how hard you can get hit, and keep moving forward-Balboa

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2876 on: June 06, 2010, 04:27:18 pm »
Can someone draw for me an isomer for pentan-1-ol CH3-CH2-CH2-CH2-CH2-OH
        OH
         |    
CH3- CH-CH2-CH2-CH3

There, :)
« Last Edit: June 06, 2010, 04:29:26 pm by Raywin »
;D

Offline mdwael

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2877 on: June 06, 2010, 04:31:47 pm »
        OH
         |    
CH3- CH-CH2-CH2-CH3

There, :)

That makes sense, thank u
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Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2878 on: June 06, 2010, 04:33:49 pm »
That makes sense, thank u
remember to write the name

PENTAN-2-OL
NO secrets to SUCCESS , it is the result of 1.HARD WORK 2.GOOD PREPARATION 3.LEARNING FROM FAILURE
But it ain't how hard you hit; it's about how hard you can get hit, and keep moving forward-Balboa

Offline Dana

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2879 on: June 06, 2010, 04:35:11 pm »
you guys when they tell us to describe a way to make a salt like lead nitrate, how do we know which one to put in excess, the lead oxide or the nitric acid??