6. How many ions of Na are in 45.6 g of Na2SO4?

3.85 ×10²³ Na⁺ ions

Explanation:

Given data:

Mass of Na₂SO₄ = 45.6 g

Number of ions of Na = ?

Solution:

Number of moles of Na₂SO₄:

Number of moles = mass/ molar mass

Number of moles = 45.6 g/ 142.04 g/mol

Number of moles = 0.32 mol

1 mole of Na₂SO₄ contain 2 moles of Na⁺ ion.

0.32 mol × 2=  0.64  moles of Na⁺ ion

1 mole contain 6.022×10²³ Na⁺ ions

0.64 mol × 6.022×10²³ Na⁺ ions / 1 mol

3.85 ×10²³ Na⁺ ions

the answer is 75.0%.