A pure copper cube has an edge length of 1.42 cm. How many copper atoms does it contain? (volume of a cube = (edge length)3; density of copper = 8.96 g/cm3)

Solution 103P

Step 1:

Given :

Edge length of Cu cube = 1.42 cm

Volume of a cube(V) = (edge length)3 = (1.42cm)3 = 2.86 cm3

Density of copper() = 8.96 g/cm3.

Number of copper atoms the cube contains = ?

We are given the density and volume, let’s calculate the mass of the copper using the density formula :

=

m = V

m = 25.62 g

Therefore the mass of the copper in the copper cube is 25.62 g.