Answer:
1.6×10^3 KJ
Step-by-step explanation:
We must first calculate the number of moles corresponding to 650.50g of sulphur trioxide.
Number of moles = mass of sulphur trioxide/ molar mass of sulphur trioxide
Molar mass of sulphur trioxide= 80.066 g/mol
Given mass of sulphur trioxide= 650.50g
Number of moles = 650.50g / 80.066 g/mol
Number of moles = 8.124 moles of sulphur trioxide
Now from the balanced reaction equation;
Formation of 2 moles of sulphur trioxide evolves 396.8KJ of energy.
Therefore formation of 8.124 moles of sulphur trioxide will evolve;
8.124moles × 396.8 KJ /2 moles = 1611.8KJ or 1.6×10^3 KJ