How many atoms of each element are present in Si (SO4)3 Ca(OH)2

3.2 moles of K2SO3

4 moles of oxygen

1.156x10²⁵ atoms and 4.8x10²⁴ atoms of oxygen

Explanation:

1 mole of a molecule X contains 6.022x10²³ molecules. In a molecules as H₂O, for example, there are 3 atoms (2 of H and 1 of O).

Thus, in 1 molecule of K₂SO₃ there are 6 atoms (2 of K, 1 of S, 3 of O). In 3.2 moles there are:

3.2mol K₂SO₃ * (6.022x10²³ molecules / 1mol) = 1.927x10²⁴ molecules.

The atoms are:

1.927x10²⁴ molecules * (6atoms / molecule) =

1.156x10²⁵ atoms

In 4 moles of oxygen, O₂, there are 2 atoms per molecule :

4mol * (6.022x10²³ molecules / mol) = 2.4x10²⁴ molecules * (2atom / molecule) =

4.8x10²⁴ atoms of oxygen

c is the answer because when something is left after something evaporates that shows the chemical change.