Answer : The energy released by the decay of 3 grams of 'Th' is 
Explanation :
First we have to calculate the mass defect
.
The balanced reaction is,

Mass defect = Sum of mass of product - sum of mass of reactants


conversion used : 
Now we have to calculate the energy released.



The energy released is 
Now we have to calculate the energy released by the decay of 3 grams of 'Th'.
As, 230 grams of Th release energy = 
So, 3 grams of Th release energy = 
Therefore, the energy released by the decay of 3 grams of 'Th' is 
The new volume : V₂ = 2454.8 L
<h3>Further explanation</h3>
Given
V₁=2240 L
P₁=760 mmHg
T₁=320 K
P₂=700 mmHg
T₂=323 K
Required
Volume V₂
Solution
Combined gas law :
P₁V₁/T₁=P₂V₂/T₂
Input the value :
760 mmHg x 2240 L /320 K = 700 mmHg x V₂/323 K
V₂=(P₁V₁T₂)/P₂T₁
V₂=(760 x 2240 x 323)/(700 x 320)
V₂ = 2454.8 L
I think the answer is hydrosphere
The balanced chemical equation is P4+3O2--> 2P2O3