Concept explainers
(a)
Interpretation:
Whether lactose is dextrorotatory or levorotatory compound should be determined.
Concept Introduction:
Chiral or optically active molecules can rotate plane-polarized light either clockwise or counter clockwise. If plane-polarized light is rotated clockwise then it is known as dextrorotatory and for counter clockwise rotation it is known as levorotatory.
(b)
Interpretation:
Specific rotation of the enantiomer of lactose should be determined.
Concept Introduction:
Enantiomers rotate the plane-polarized light in opposite directions by same angle.
(c)
Interpretation:
The amount of lactose enantiomer dissolved in water should be determined.
Concept Introduction:
Physical properties of enantiomers are similar except the direction of optical activity. Solubility, melting point, boiling points are similar.
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