Sodium sulfate 10−hydrate, Na₂SO₄·10H₂O, dehydrates according to the equation

a) Na₂SO₄·10H₂O ⇌ Na₂SO₄ + 10H₂O
b) Na₂SO₄ + 10H2O ⇌ Na2SO4·10H2O
c) Na₂SO₄·10H₂O ⇌ Na₂SO₄ + H₂O
d) Na₂SO₄ + H₂O ⇌ Na₂SO₄·10H₂O