This chemical equation represents a chemical reaction. 2HNO3+Na2SO3-2NaNO3+H2O+SO2

D. Na₂SO₃

Explanation:

The given equation is:

         2HNO₃ + Na₂SO₃  → 2NaNO₃  + H₂O + SO₂

The reaction equation is shown above. In chemical reactions, the left hand side is made up of the reactants and the right hand side is made up of the products.

 The reactants in the equation are:

     HNO₃ and Na₂SO₃

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

a) the particles of the chair are strongly held together.