Determine the number of cobalt atoms in a 117.86 g sample of cobalt

12.04 * 10²³ atoms

Explanation:

Given dа ta:

Mass of cobalt = 117.86 g

Number of atoms = ?

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms, ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 * 10²³ is called Avogadro number.

For example,

Number of moles of cobalt = 117.86 g / 58.9 g/mol

Number of moles of cobalt = 2 mol

one moles of cobalt = 6.022 * 10²³ atoms of cobalt

2 moles * 6.022 * 10²³ atoms / 1 mol

12.04 * 10²³ atoms