Meso Compounds

Q.

What is a stereo center and a chiral center?

Q. Amongst the given options the compounds(s) in which all the atoms are in one plane in all the possible conformations (if any), is (are)

1. $H_{2}C=C=O$
2. $H-2C=C=C{H}_2$
3. 
4. 

Q. Which of the following will show geometrical?
1.
2.

3.
$ClBrC=C=C=C\left(C{H}_3\right)\left(C_2{H}_5\right)$
4.
$C{H}_{3}HC=C=CBrH$

1. 1, 2, 3
2. 2, 3 only
3. 3, 4 only
4. 2, 3, 4

Q. atmost how many isomer can bromohexane have ?

Q.

How would you convert ethanol into ethane.

Q. 29.The value of ebullioscopic constant depends upon?? And how??

Q.

A compound whose molecule is superimposable on its mirror image despite containing chiral carbon atoms is called:

1. Threo isomer

2. Meso compound

3. No special name

4. Enantiomer

Q.
The number of chiral centres present in the above compound is

1. \N
2. 1
3. 2

Q. If the specific rotation of optically pure 2-Butanol is -120 degrees, and a synthetic sample of 2-butanol containing both the enantiomers shows a specific rotation of +24 degrees, find the percentage of d-2-Butanol.

1. 80
2. 40
3. 20
4. 60

Q. Which of the following structure(s) is/are meso-2, 3 butanediol?

1. 
2. 
3. 
4. 

Q.

Does 1, 2 dimethylcyclopropane exhibit optical isomerism?if no...why?if yes...why?

Q. An optically active alcohol A$\left(C_6{H}_{10}O\right)$ absorbs two moles of hydrogen per mole of A upon catalytic hydrogenation and gives a product B.The compound B is resistant to oxidation by $Cr{O}_3$ and does not show any optical activity.Deduce the structures of A and B.

1. 
2. 
3. 
4. 

Q. Which of the following is the most stable conformer of the given molecule?

1. 
2. 
3. 
4. 

Q. 22.Bromobenzene from iodobenzene

Q. The following compound is a meso compound – True or False?

1. True
2. False

Q. 11. What is the monomer of CH2C(CH3)2CH2C(+)(CH3)2 ?

Q. What is the effect of elctron releasing group and electron withdrawing group in coupling rxn of benzene diazoniumhalide?

Q. Which of the following will have a meso isomer?

1. Cis-1, 2 dichlorocyclobutane
2. 2, 3 - dichlorobutane
3. 2, 2-dichlorobutane
4. 2, 3-dimethylbutane

Q. Why is (-)-butan-2-ol is optically inactive?

Q. Total number of structural isomers with the formula $C_3{H}_4$ is:

1. 2
2. 5
3. 3
4. 4

Q. Optical rotation of sucrose in $1$ $N$ $HCl$ at various times was found as shown below:
$\begin{array}{cccccc}Time\left(sec\right)& 0& 7.18& 18.0& 27.05& \infty \\ Rotation\left(deg\right)& +24.09& +21.7& +17.7& +15.0& -10.74\end{array}$
Show that the inversion of sucrose is a first order reaction.

Q. Meso compound do not show optical activity because :

1. they do not contain plane of symmetry
2. they have non-super imposable mirror images
3. they do not contain chiral carbon atoms
4. they contain plane of symmetry

Q. Match the following according to their optical activity.

1. always active
2. sometimes active
3. always inactive

Q. Meso compounds can be planar.

1. True
2. False

Q. Which of the following compounds are meso?

1. 
2. 
3. 
4. 

Q. Why is N-methyl, N-ethyl propylamine optically inactive?Is it because something called pyramidal inversion?If yes , what is pyramidal inversion?

Q. Which of the following structure(s) is/are meso-2, 3 butanediol?

1. 
2. 
3. 
4. 

Q. Match the following according to their optical activity.

1. always active
2. sometimes active
3. always inactive

Q. Meso tartaric acid is optically inactive due to the presence of:

1. molecular asymmetry
2. molecular symmetry
3. external compensation
4. two asymmetric C-atoms

Q. Statement 1 : Butan-2-ol is optically active.

1. Statement 1 is correct
2. Both 1 and 2 are correct
3. Statement 2 is correct
4. Both 1 and 2 are incorrect