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BTW reduction is the action or fact of making a specified thing smaller or less in amount, degree, or size.
Answer:the amount of matter the object contains
Explanation:
The boiling point depends on the strength of the intermolecular forces holding the molecules together. Greater the force, higher is the boiling point.
The intermolecular force increases in the order shown below:
ion-ion > H-bonding > dipole-dipole > London dispersion
CH3CN is a polar molecule with strong dipole-dipole forces
CH3CH2CH3 is non-polar held by london dispersion
Ar exist as a gas. It will have a lowest boiling point
Thus the order of decreasing b.pt is:
CH3CN > CH3CH2CH3 > Ar