3.95x10^25 atoms Cu2S to grams

Mass = 10440.9 g

Explanation:

Given dа ta:

Number of atoms of Cu₂S = 3.95*10²⁵

Grams of Cu₂S = ?

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,

18 g of water = 1 mole = 6.022 * 10²³ molecules of water

1.008 g of hydrogen = 1 mole = 6.022 * 10²³ atoms of hydrogen

Now we calculate the number of moles from given number of atoms.

3.95*10²⁵ atoms / 6.022 * 10²³ atoms * 1 mol

0.656*10² mol

65.6 mol

Now we will calculate the mass:

Mass = number of moles * molar mass

Mass = 65.6 mol * 159.16 g/mol

Mass = 10440.9 g