Verified Answer :

Density is a value for
mass, such as kg, divided by a value for volume, such as m3. Density is a
physical property of a substance that represents the mass of that substance per
unit volume. To find the mass of the substance, we need to multiply the volume occupied by the substance.

Mass = Density x Volume
Mass = 7.9 g/cm^3 (5.5 cm)^3
Mass = 43.45 g 

Answer:

Mass, m = 1.31 kg

Explanation:

It is given that,

Density of iron, \(d=7.9\ g/cm^3\)

Side of cube, a = 55 mm = 5.5 cm

We need to find the mass of the cube of iron. Mass per unit volume is called the density of the substance. It is given by :

\(d=\dfrac{m}{V}\)

\(d=\dfrac{m}{a^3}\)

\(m=d\times a^3\)

\(m=7.9\times (5.5)^3\)

m = 1314.36 grams

or

m = 1.31 kg

So, the mass of the iron cube is 1.31 kg. Hence, this is the required solution.