Write total fuctional isomers of molecular formula C5H10O.

Total fuctional isomers of molecular formula C₅H₁₀O Possible are six which are given as:

Arrange the following compounds 2-Methylhexane in order of their increasing of (A) boiling point and (B) melting point ? (1) n-hexane (2) 2-methyl hexane (3) 2, 2-dimethyl pentane (4) 2, 3-dimethyl pentane.

(A) BoiIing point on alkane is directly proportional to their molecular weight and  inversely proportional to branching. Therefore, the increasing order is (1) < (3) < (4) < (2)   

(B) Melting point of alkane is directly proportional to molecular weight as well as branching of  alkane because increased branching leads to a more compact molecule. Thus the increasing order is (1) < (2) < (4) < (3). 

Benzamide is less easily hydrolysed than methyl benzoate. Why ?

We know that N is less electronegative than oxygen therefore. N can donate a pair of electrons more readily than oxygen.  Therefore, magnitude of positive charge on carbonyl carbon in benzamide is less than in methyl benzoate. Thus during hydrolysis, attack of -OH- ion on carbonyl carbon in benzamide is difficult than in methyl benzoate. Thus benzamide is less easily hydrolysed than methyl benzoate.