Question

2Na₂SO₃(aq) + 2HNO₃(aq) => 2NaNO₃(aq) + SO₂(g) + H₂O

deltha H = 433 kJ

In an experiment, 15.5 g of HNO₃ is completely reacted with excess sodium sulfite according to the equation above. How much heat is exchanged (in kJ) when this happens Enter the numerical answer with +/- sign. Use correct number of sig figs!

Answer 1

The heat exchanged when 15.5 g of HNO₃ is completely reacted with excess sodium sulfite is approximately 26.9 kJ.

Step-by-step explanation:

In the given reaction, 2Na₂SO₃(aq) + 2HNO₃(aq) => 2NaNO₃(aq) + SO₂(g) + H₂O, the heat exchanged is given as 433 kJ. To calculate the amount of heat exchanged when 15.5 g of HNO₃ is completely reacted, we need to use the molar mass of HNO₃. The molar mass of HNO₃ is approximately 63.01 g/mol.

First, we need to calculate the number of moles of HNO₃:

(15.5 g)/(63.01 g/mol) = 0.246 mol

Since the coefficients in the balanced equation indicate that 2 moles of HNO₃ react with the other reactants, we can set up a proportion to find the heat exchanged:

(0.246 mol)/(2 mol) = (x kJ)/(433 kJ)

Solving for x, we find that x = 26.9 kJ.