Question

1.

Answer 1

Answer:

1. a) 0.745 g of H₂SO₄

b) 97.4%

2.  1.28×10²⁴ formula units

Explanation:

First of all, we determine the equations:

3Na₂SO₄   +  2H₃PO₄  →  3H₂SO₄  +  2Na₃PO₄

We determine, the moles of sodium sulfate. (As the acid is in excess, we work with the salt)

1.08 g . 1mol/ 142.04g = 0.00760 moles.

Ratio is 3:3. So 3 moles of salt can produce 3 moles of sulfuric acid,

Then, 0.00760 moles will produce the same amount of acid.

We convert the moles to mass → 0.00760 mol . 98 g/mol = 0.745 g

Percent yield = (Produced yield /Theoretical yield) . 100

(0.726 g / 0.745 g) . 100 = 97.4 %

2. 3 moles of sodium sulfate need 3 moles of phosphoric acid to react

Then, 3.2 moles of salt will react to (3.2 . 2)/3 = 2.13 moles

Let's count the formula units:

2.13 mol . 6.02×10²³ formula units /mol = 1.28×10²⁴ formula units.