How many chiral centers are in the following compound A 4 B 5 C 6 D 7?

Answer

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(R) and (S) Nomenclature of Asymmetric Carbon Atoms
Chiral Compounds Without Asymmetric Atoms
Fischer Projections and Diastereomers
Meso Compounds
How many chiral centers are in the following compound?
How do you know how many chiral centers there are?
How many stereoisomers does 4 chiral centers have?

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Hint: A molecule is said to be chiral if it is not superimposable on its mirror images. Optical activity is the ability of a chiral molecule to rotate the plane polarized light. Chirality often leads to optical activity in a compound, but it is not a necessary condition for optical activity.

Complete step by step answer:
Chirality is not just reserved for objects. Molecules can also be chiral. Chiral molecules are the molecules having an asymmetrical center. An asymmetric center means that a tetrahedral atom bonded to four different groups or atoms.
Chiral objects are objects with left handed and right handed forms. Non-superimposable mirror image is a mirror image that is not the same as the image itself. Chiral objects have non-superimposable mirror images.
A chiral center is a point in a molecule where four different groups are bonded. If two groups are the same, then it is not chiral. A chiral molecule usually has at least one chiral center.
For example, in a compound named bromo chloro fluoro iodo methane. The chiral center is at the carbon atom. It is bonded to four different atoms, i.e. bromine, chlorine, fluorine and iodine.

Chiral centers are mark with an asterisk (*). There are six chiral centers which are bonded to four different groups.

Note:
Chiral centers are also known as stereogenic centers. When the mirror image of an achiral carbon is rotated, and the structure can be aligned with each other, their mirror images are said to be achiral. Fischer projection is a two dimensional representation of a three dimensional molecule. This is more helpful for checking whether there is a chiral carbon atom or not.

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6-1 For the following compounds, star (*) each chiral center, if any.

6-2 For the following compounds, identify the R or S configuration of each chiral carbon atom.

6-3 Draw out the following molecules, including stereocenters.

a) (2R,4S,6R)-2-bromo-6-chloro-4-methylheptane

b) (4R)-4-bromopent-1-ene

c) (1R,2R,3S)-1-fluoro-2,3-dimethylcyclohexane

d) (3S)-3-methylcyclopent-1-ene

(R) and (S) Nomenclature of Asymmetric Carbon Atoms

6-4 For the following compounds, assign R or S configurations for each stereocenter.

6-5 For the following compounds, assign R or S configurations for each stereocenter.

6-6 Identify each molecule as either (R)- or (S)-Limonene.

Chiral Compounds Without Asymmetric Atoms

6-7 Explain why the following compound is optically active.

6-8 Does the following compound contain a chiral center? Is it a chiral molecule?

6-9 Why is this biaryl compound shown below considered chiral, despite having no chiral center?

Fischer Projections and Diastereomers

6-10 For the following Fischer projections, identify the configuration (R or S) of all chiral centers (some atoms may not be chiral centers).

6-11 For the following pairs of compounds, identify whether they are enantiomers, diastereomers, or the same compound.

6-12 For the following pairs of compounds, identify whether they are enantiomers, diastereomers, or the same compound.

Meso Compounds

6-13 For the following compounds, identify whether they are meso or not meso.

6-14 Are meso compounds optically active? Explain your answer.

6-15 Is the following compound meso or not meso?

How many chiral centers are in the following compound?

There are six chiral centers which are bonded to four different groups. Note: Chiral centers are also known as stereogenic centers. When the mirror image of an achiral carbon is rotated, and the structure can be aligned with each other, their mirror images are said to be achiral.

How do you know how many chiral centers there are?

The key to finding chiral carbons is to look for carbons that are attached to four different substituents. We can immediately eliminate any carbons that are involved in double bonds, or that have two hydrogens attached. Given this, we find that there are three chiral carbons.

How many stereoisomers does 4 chiral centers have?

Each time we add a chiral center to a molecule, we double the possible number of stereoisomers. With 1 chiral center, there are 2 isomers, 2 chiral centers, 4 possible isomers, 3 centers, 8 isomers and 4 centers, 16 possible stereoisomers.