Select the correct answer.
which statement describes both homogeneous mixtures and heterogeneous mixtures?

a.
their components can be distinguished visually.
b.
their components are combined in a fixed ratio.
c.
their components can be separated by physical processes.
d.
they always contain a liquid component.
e.
they are considered to be pure substances.

C. Their components can be separated by physical processes.  

Explanation:

The components of any mixture can be separated by physical means.

A. is wrong. This is a property of heterogeneous mixtures.

B. is wrong. This is a property of compounds.

D. is wrong. For example, air is a mixture of gases and brass is a mixture of solids.

E. is wrong. Only elements and compounds are pure substances.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3