3. Find the mass of 4.77 x 1022 atoms of scandium

(Sc).

Mass = 3.6 g

Explanation:

Given dа ta:

Number of atoms of scandium = 4.77*10²² atoms

Mass of arsenic = ?

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.

one mole = 6.02*10²³ atoms

one mole * 4.77*10²² atoms / 6.02*10²³ atoms

0.08 mol

Mass of scandium

Mass = number of moles * molar mass

Mass = 0.08 mol * 45 g/mol

Mass = 3.6 g