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Chemistry: Post your doubts here!

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What's that reaction involved with KMnO4 and alchohols? I can't seem to understand. Please help me I need an answer desperately
its the oxidaton reaction a primary alcohol(if completelyoxidised under Hot concentrated condition) is oxidised 2 a carboxyhlic acid .....if incomplte oxidise(cold dilute) then can form aldehyde.......secondory alcohols are just oxidised 2 ketones in both conditions.....
 
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What's that reaction involved with KMnO4 and alchohols? I can't seem to understand. Please help me I need an answer desperately
KMnO4 oxidises alcohols to aldehydes or ketones, and then rapidly oxidises the aldehyde to a carboxylic acid if you let it react.
 
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its the oxidaton reaction a primary alcohol(if completelyoxidised under Hot concentrated condition) is oxidised 2 a carboxyhlic acid .....if incomplte oxidise(cold dilute) then can form aldehyde.......secondory alcohols are just oxidised 2 ketones in both conditions.....
but isnt that with K2Cr2O7, acidified with dil H2SO4?
 
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I'm soo doomed.. I don't know how to answer most of the questions... I don't know what to do. ::cry:
 
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Ermm anybody got tips for MCQ exams?
All the choices look so alike,and the calculations are </3 :'(

-Start backwards. It saves time.
-Use process of elimination. You may not know what is correct, but you might know what is wrong, so don't worry about those options and focus on the others. (Especially useful in the last 10 questions)
-Use trial and error. Where possible, plug in the values from answers, and work the equation backwards to figure out which one is correct.
 
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I'm soo doomed.. I don't know how to answer most of the questions... I don't know what to do. ::cry:

Its alright, all you can do now is try understanding what people are posting and the answers or go through some of the notes. Don't get tensed AT ALL ! it wont help in any way.. relax whatever you know just do it tmrw and whatever you can do nw just do it may it be little. Something is better than nothing. There are many in the same situation. Just an advice :)
 
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the answer is C since the moles of CO2 produced=atoms of CO2:
1mol=24dm3thus 24000cm3
mols that occupy 72cm3=72/24000
moles that occupy72cm3=3*10^-3
so carbon atoms=3*10^-3
mass of this carbon atoms= 3*10^3*12(mr)
mass=.036g
mass of almunium=mass of compund-mass of carbon atoms
mass of almunium=.144-.036=.108
moles of Al=mass/Mr
moles=.108/27=4*10^-3
mole ratio of Al:C ------>4*106-3:3*10^-3
thus simple ratio is 4:3
so compound is Al4C3
 
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the answer is C since the moles of CO2 produced=atoms of CO2:
1mol=24dm3thus 24000cm3
mols that occupy 72cm3=72/24000
moles that occupy72cm3=3*10^-3
so carbon atoms=3*10^-3
mass of this carbon atoms= 3*10^3*12(mr)
mass=.036g
mass of almunium=mass of compund-mass of carbon atoms
mass of almunium=.144-.036=.108
moles of Al=mass/Mr
moles=.108/27=4*10^-3
mole ratio of Al:C ------>4*106-3:3*10^-3
thus simple ratio is 4:3
so compound is Al4C3
thankyou
 
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