Combustion of 1,2 chloro propane

[aommaster]

Hi guys!

 

In my chemistry course, we learnt different reactions of halogenoalkanes, such as substitution reactions, and elmination reactions.

 

One of the reactions that came up was a combustion reaction. What are the products of teh reaction if the substance is burnt completely in air.

 

I know that water and carbon dioxide are produced, but what happens to the chlorine, or the halogen that is attatched to the chain?

 

I did a quick lab test, in which I used litmus paper, and there was certainly an acid produced. But which one?

 

Thanks alot for your help!

[woelen]

Hi guys!

 

In my chemistry course' date=' we learnt different reactions of halogenoalkanes, such as substitution reactions, and elmination reactions.

 

One of the reactions that came up was a combustion reaction. What are the products of teh reaction if the substance is burnt completely in air.

 

I know that water and carbon dioxide are produced, but what happens to the chlorine, or the halogen that is attatched to the chain?

 

I did a quick lab test, in which I used litmus paper, and there was certainly an acid produced. But which one?

 

Thanks alot for your help![/quote']

Chlorinated hydrocarbons usually burn with a lot of soot. The more halogen is attached to the carbons, the more soot is produced. If they are burned completely (which is not easy at all), then you'll get H2O, CO2 and HCl.

 

E.g. CH2ClCHClCH3 + 4O2 --> 3CO2 + 2H2O + 2HCl

 

This HCl also is the cause of the very pungent smell, which can be observed if you are near a place, where chlorinated hydrocarbons are burning.

[aommaster]

Ok, I thought the acid prduced was hydrogen chlorate (HClO3). Is that a possibility, since you hace plenty of oxygen for the reaction to occur?

[woelen]

Ok, I thought the acid prduced was hydrogen chlorate (HClO3). Is that a possibility, since you hace plenty of oxygen for the reaction to occur?

No, that is not possible. The acid HClO3 is not stable and only exists in dilute aqueous solution. On concentration, it decomposes, giving Cl2, H2O, ClO2 and O2. Under the combustion conditions with plenty of oxygen available, the only really stable chlorine compound is HCl.

[YT2095]

if memory serves me correctly, the incomplete combustion of such halokane liberates phosgene gas (that used in WWII to kill people).

 

carbonyl chloride or something like that.

[woelen]

if memory serves me correctly' date=' the incomplete combustion of such halokane liberates phosgene gas (that used in WWII to kill people).

 

carbonyl chloride or something like that.[/quote']

Yes, you're right. The formula is COCl2. Good that you mention this. I already made a remark that it is hard to have complete combustion, but it is good to add this warning .

[aommaster]

Thanks alot for your help guys. Nice bit of information provided by YT! Thanks!