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Chemistry: Post your doubts here!

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N 2011 q13 q24 q29 q30 q31 q34 q37 q38 q39

Can u plz solve these questions for me?? :)
 
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29B as the dibromoalkane formed will form a diol as each bromine will be substituted by a OH ion
 
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13c as they contain the common oxide of all three element hydrogen carbon and sulpher
24c as in first reaction is nuclophylic substitution in which C=O will be replaced with a c-cN and OH bond then H2SO4 oxidised the CN to CO2H and then it formed a ester of the formulae given
in 13 i am confused y H2S or SO3 will not be formed? o_O
 
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13c as they contain the common oxide of all three element hydrogen carbon and sulpher
24c as in first reaction is nuclophylic substitution in which C=O will be replaced with a c-cN and OH bond then H2SO4 oxidised the CN to CO2H and then it formed a ester of the formulae given
in the 24th question ... nitriles are oxidised to form acids right?? why is there a branching (OH) chain too?? that's wat confused me in this question... :confused:
 
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in 13 i am confused y H2S or SO3 will not be formed? o_O
well you are burning the compound in air and they will break and oxidise them selves instead of reacting between themselves :)
and SO3 requires certain conditions or a very STRONG oxidising agent as SO2 will not oxidise easily
 
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29B as the dibromoalkane formed will form a diol as each bromine will be substituted by a OH ion
oo i just confirmed all three answers... only 13th is ryt...
24's answer is actually B
and 29's answer is D
 
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well you are burning the compound in air and they will break and oxidise them selves instead of reacting between themselves :)
and SO3 requires certain conditions or a very STRONG oxidising agent as SO2 will not oxidise easily
oh okaay thanks :)
 
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n
in the 24th question ... nitriles are oxidised to form acids right?? why is there a branching (OH) chain too?? that's wat confused me in this question... :confused:
not branching Br are attached to two different Cs hence OH will also do the same hence they look branched
 
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ummm okay but now tell me about q24 too :p u explained Q29 :p
Q24 the answer will be B because see..

CH3CHO + HCN -----> CH3H(OH)CN
CH3CH(OH)CN + dil. H2SO4 ----> CH3CHCOOH (hydrolysis of nitriles forms acid)

acid + alcohol will give u an ester so CH3CH(OH)COOH + CH3OH ----> CH3CH(OH)CO2CH3 so the answer is B

did u get it ?
 
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Q24 the answer will be B because see..

CH3CHO + HCN -----> CH3H(OH)CN
CH3CH(OH)CN + dil. H2SO4 ----> CH3CHCOOH (hydrolysis of nitriles forms acid)

acid + alcohol will give u an ester so CH3CH(OH)COOH + CH3OH ----> CH3CH(OH)CO2CH3 so the answer is B

did u get it ?
yeah I'm just confused by the (OH) in the ester... i mean there is an alcohol group on the ester?? :confused: how does that work out?!! :eek:
 
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yeah I'm just confused by the (OH) in the ester... i mean there is an alcohol group on the ester?? :confused: how does that work out?!! :eek:
what's wrong with that? it doesn't matter and it can't react with the alcohol because they r both alcohols..compounds like these r called 'hyrdoxy' so this one will be called
2-hyrdoxy methyl propanoate (i guess thats the correct name) but alll what i want to tell u that it doesn't matter since there is a carboxylic acid group already reacting with an alcohol group then definitely we will have an ester..got me ?
 
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what's wrong with that? it doesn't matter and it can't react with the alcohol because they r both alcohols..compounds like these r called 'hyrdoxy' so this one will be called
2-hyrdoxy methyl propanoate (i guess thats the correct name) but alll what i want to tell u that it doesn't matter since there is a carboxylic acid group already reacting with an alcohol group then definitely we will have an ester..got me ?
ohh okay -_- yeah i got u now.... gosh i cud just blow up organic chem if i got the chance!! every question seems to be an alien !! -_- x.x
Thankss btw for ur help... i'll b needing a lot of it especially in the organic section over the next couple of days ^_^
 
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CH3CH(OH)CN > CH3CH(OH)COOH > CH3CH(OH)COOCH3

Answer B
ohh thanks.... that means.... no matter wat is dangling from the rest of the chain most of the times our main focus will be on the funtional group only. ryt?
 
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