Is milk a pure substance?

Select one from the following options:

A)No

B)Yes

C)Never

D) Sometimes

Answer:(A)

Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.

So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.

In milk, we get more than one elements and compounds.So milk is neither a single compound nor a single element.As a result, it is not a pure substance.It doesn't have a definite and fixed composition.Actually,it is a mixture.In milk,we get water, protein,minerals etc.