Newbie need help on Organic Chemistry

[Dc Nilbog]

Hi there, i've just registered with these forums, so this is my first post. I thought this would be a great place to aid me on my scientific career, so firstly I just wanna say Hi.

 

Secondly, well, the main point of this post is because I am stuck on an Organic Question; questions that I need to answer in a laboratory report write-up.

 

Here are the methods that were executed during the experiment:

 

[size="3"][font="Arial"][b]PREPARATION OF AN ALKYL HALIDE (N-BUTYL BROMIDE)[/b][/font] [/size]

>This preparation involves the conversion of an alcohol (1-butanol) to a haloalkane (1-bromobutane).

[font="Arial"]Equation for this experiment:[/font]

                                 H+
CH3(CH2)3OH + Br-      ----->      CH3(CH2)3Br + OH-

[font="Arial"]----- Procedure -----[/font]

a) Water (10mL), sodium bromide (9g) and n-butanol (7mL) was put into a round bottom flask.
b) Later, concentrated sulphuric acid was gradually added to the flask.
c) This mixture of liquids was put into a reflux condenser to distill for about 30min.
d) The mixture was allowed to cool to room temperature, and the apparatus was then rearranged for distillation.
e) This mixture was re-distillated until there were no more oily droplets appearing in the condensate.
f) The distillate formed was put into a separating funnel. At this stage, water was added to the mixture and then water layer was discarded, while the lower layer 1-bromobutane was drawn off into a small conical fask after each washing.
g) The last traces of acid was removed from the distillate by washing with dilute sodium carbonate. This was poured out into a conical flask.
h) About 2g of anhydrous calcium chloride was added to the flask to remove the last traces of water. This sample was shook intermittently for about 15 minutes.
i) The mass of a conical flask was measured. The product from the previous distillate was re-distilled using a dry apparatus which was distilled at 97-102'C. 
j) The yield was weighed.

 

 

Here are my questions:

 

1) In the first distillation of the crude product from the reaction mixture, water distilled over with the product. If the temperature had been recorded it would have been about 90 degrees Celcius. Comment on this.

 

2) Two other minor impurities in the crude product are but-1-ene and di-n-butyl ether. How are these formed? Find out their boiling points and assess the ability of the above purification process to remove these impurities.

 

 

 

>I would be very appreciated if anyone could help me answer these questions or even comment on my procedure write up punctuation/grammar/content (this procedures part is just a rewrite of what is in my study manual).

 

>I am currently doing a first year organic paper and I am not really that top of my game at the moment. If you are explaining something, please make it easier for me to understand.

 

 

Thank you very much for your help

 

Dc Nilbog

[YT2095]

conc sulphuric will create ethers,from alcohols, what is conc sulphuric acid known for doing to organic materials?

 

also part: g) The last traces of acid was removed from the distillate by washing with dilute sodium carbonate. This was out into a conical flask.

 

needs some work

[Dc Nilbog]

Thanks for your response YT2095, you said:

 

> conc sulphuric will create ethers,from alcohols, what is conc sulphuric acid known for doing to organic materials?

 

Dehydration? Hmm... Sounds right. Thanks!

 

>Some Grammar mistakes fixed. Thanks.

 

 

 

Any clue about question 1? Thanks for your responses.

Dc Nilbog

[YT2095]

you could do worse than looking up the word "Azeotrope"

[Dc Nilbog]

Thanks for the help YT2095. +rep to you.

I did not explicitly explain the tiny details in my report, too much content for me to follow, I handed it in though.

 

 

Dc Nilbog

[YT2095]

Thanks!

 

and you`re quite Welcome