Answer:
Na₂SO₄•(H₂O)₆.
Explanation:
The mass that is lost when the sample is heated is water.
Let's assume we have 100 g of the hydrate:
43 grams would be water (H₂O), while the rest (100-43=57) would be sodium sulfate anhydrous (Na₂SO₄).
We convert both those masses to moles, using their respective molar masses:
- H₂O ⇒ 43 g ÷ 18 g/mol = 2.39 mol
- Na₂SO₄ ⇒ 57 g ÷ 142.04 g/mol = 0.40 mol
We can write those results as (Na₂SO₄)₀.₄₀•(H₂O)₂.₃₉. Now we just need to multiply those numbers so that they become integers.
If we multiply both coefficients by 5 we're left with (Na₂SO₄)₂•(H₂O)₁₂.
Simplify and thus the final answer is Na₂SO₄•(H₂O)₆.
