I uploaded a file with some Orgo questions I had and also my thoughts highlighted in blue. Please let me know your thought process on these questions. In some cases I don't understand why the circled ans is chosen. There are no explanations hence the reason for asking. These are just random Orgo questions that I picked from websites over the internet. Thanks!
Some Orgo questions...
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Thank you bud. I appreciate your responses and sharing your thought process. I agree with your analysis. There were gotchas on my end esp., with the order of acidity with H not attached to the halogen. I missed that part - and the complete octet rule which I failed to consider while analyzing those structures. Thanks for pointing those out.
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Q3-
Ø In structure I all are with completed octet even Oxygen with positive charge has 8 electrons but in structure ii C is with 6 electrons. Completed octet is more important rule.
Q Ø I was able to eliminate choices ‘c’, ‘e’, ‘a’. The ans had to be either ‘d’ and ‘b’. What could I have seen in the spectrum to rule out ‘d’. One afterthought I had was the peak in 1450 region which could mean C=C. Is that correct?
Did you calculate degrees of unsaturation (Index of Hydrogen)for the molecule.
DOU=(2#C+2 - #H)/2 = (2x6+2-10)/2= 2
It means the molecule must have either two double bonds or a ring with one double bond or a triple bond.
D molecule has only one degree of unsaturation as it has only one double bond.
In Q9
The correct lewis diagram is H-C triple bond O with one lone pair and a formal positive charge(sorry I dont know how to share the URL of the image).So carbon is sp hybridized and H-C-O angle is 180 degree.
Q10 Your are absolutely right .Energy is inversely proportional to wavelength and Absorption is going from low energy to high energy.
In Q11 you are forgetting about 1,3 -diaxial interaction which is there is 1,3-trans(ii molecule).1,3 -diaxial interaction is more stronger repulsion .
Q11 You are right acidity increases down the group but when acidic H is bonded directly with the atoms of the group.
like
H-I>H-Br>H-Cl>H-F
however in your questions -acidic H is on oxygen in all molecules and then we need to compare the electron withdrawing effect of the halogens.More electron withdrawing group can make Oxygen to which acidic hydrogen is bonded more electron deficient which in turn will pull electrons from acidic H. Hence making its release as H+ ions more easier.
I hope this will help you.
Thanks
