Respuesta :

Diatonic254

6.9988 x 10²³

Explanation:

We begin by finding the volume of the cube;

L * W * H

2.02 * 2.02 * 2.02

= 8.242408 cm3

If the density of copper = 8.96 g/cm3, the whole cube weighs;

8.242408 cm3 * 8.96

= 73. 852 g

The molar mass of a Copper is 63.5460 g/mol.  The number Copper moles in the cube is;

73.852 / 63.5460

= 1.1622 moles

Remember the Avogadro number that states that there are 6.022×10^23 particles  per mol. Therefore the number of Copper atoms in the cube is;

1.1622 * 6.022×10^23

= 6.9988 x 10²³

Eduard22sly

The number of copper atoms in the pure copper cube is 7×10²³ atoms

We'll begin by calculating the volume of the copper. This can be obtained as follow:

Edge length (L) = 2.02 cm

Volume (V) =?

V = L³

V = 2.02³

V = 8.242408 cm³

  • Next, we shall determine the mass of the copper.

Volume = 8.242408 cm³

Density = 8.96 g/cm³

Mass =?

Mass = Density × Volume

Mass = 8.96 × 8.242408

Mass of Cu = 73.85 g

  • Finally, we shall determine the number of atoms in 73.85 g of Cu.

From Avogadro's hypothesis,

1 mole of Cu = 6.02×10²³ atoms

Recall:

1 mole of Cu = 63.5 g

Thus,

63.5 g of Cu = 6.02×10²³ atoms

Therefore,

73.85 g of Cu = [tex]\frac{73.85 * 6.02*10^{23}}{63.5}\\\\[/tex]

73.85 g of Cu = 7×10²³ atoms

Therefore, the number of copper atoms in the cube is 7×10²³ atoms

Learn more: https://brainly.com/question/15488332

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