A carbon which is attached to four different atoms or group of atoms with different environment is called as 
Chiral Carbon or 
Asymmetric Carbon.
Non-<span>
superimposable:
</span>                                     The mirror image (molecule) of chiral carbon cotaining compounds are Non.Superimposable on each other. They are called enantiomers of each other.
Polarized Light and Chiral Carbon:                                                       When a polarized light is allowed to fall on either enantiomer of chiral compound, it is rotated other clockwise or anti-clockwise.
Examples:                Below are three axamples of compounds containing chiral carbon.
 
        
        
        
Acids are donors of protons (H+) and bases are acceptors of protons.
For example:
1) hydrochloric acid (HCl) in reaction with water give one proton to water and become chloride anion (Cl-).
2) ammonia (NH3) Is base, in reaction with water accepts one protone and become ammonium cation (NH4+).
        
             
        
        
        
It’s A dalton he is the one who figured out matter
        
             
        
        
        
The answer is zero!
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