Question

Copper has a specific gravity of $8.9$ . What does it mean?

Answer 1

Density is defined as the ratio of mass per unit volume. Water has a density of $1gm{\left( {cm} \right)^{ - 3}}$ . But the density of water has an anonymous property at ${4^0}C$ as at ${0^0}C$ water exists as ice and ${4^0}C$ water exists as liquid water only. Specific gravity of any substance relates the density of substance and density of water at ${4^0}C$

Complete answer:
Copper is the chemical element with atomic number $29$ and is placed in d-block as the last electron is entering into d-orbital. It is a denser element than water which can be proved by the value of specific gravity.
The formula for the specific gravity is the ratio of density of that substance which means copper to density of reference material. Generally used reference substance is the density of water at ${4^0}C$ .
$S = \dfrac{{{\rho _{Cu}}}}{{{\rho _{{H_2}O}}at{4^0}C}}$
$S$ is specific gravity of copper
${\rho _{Cu}}$ is density of copper
${\rho _{{H_2}O}}at{4^0}C$ is density of water at ${4^0}C$
Given that the specific gravity of copper is $8.9$
It means copper is $8.9$ times denser than water at ${4^0}C$ as the specific gravity relates the density of substance density of water at ${4^0}C$
The denser compound or substance will have more density. The compounds with more density can float on the compounds with low density.

Note:
As the density of copper is more than the water which can be determined from the above explanation, it reveals that copper cannot be able to flow on water due to its more density. The general fact is metals have higher density than water, and copper is also a metal.