Question

What is the volume of a platinum ring having a mass of $5.4oz$ ?

Answer 1

The mass of the platinum is given in units of oz, where oz can be converted into grams. The density of metal is generally constant, platinum is also one of the metals. By substituting the density, and the converted mass which was in grams the volume of a platinum can be obtained.
$\rho = \dfrac{m}{V}$
$\rho$ is density of a platinum ring
$m$ is mass of a platinum ring
$V$ is the volume of a platinum ring.

Complete answer:
Periodic table consists of elements which are divided into metals, and nonmetals based on nature. Metals can easily lose electrons and undergo oxidation, and non-metals can try to gain or attain electrons and undergo reduction.
Platinum is an element with atomic number $78$ and it is a metal, it is a silvery whitish metal. It is also known as little silver.
Given that the mass of a platinum ring is $5.4oz$
$1oz$ is the unit which is equal to $28.35g$
Thus, mass of a given platinum ring is $28.35 \times 5.4 = 153.09g$
Density is constant for so many metals, density of platinum is $21.45g{\left( {cm} \right)^{ - 3}}$
Substitute these both values in the above formula,
$21.45g{\left( {cm} \right)^{ - 3}} = \dfrac{{153.09g}}{V}$
Further simplification, the volume will be $V = 7.13c{m^3}$
Thus, the volume of a platinum ring having a mass of $5.4oz$ is $7.13c{m^3}$ .

Note:
While calculating the volume, when the mass is in grams, the density must be in the units of grams per centimeter cube only. oz is the unit used to express the mass of any substance, it should be converted into grams firstly and then only substituted.