nitroglycerin decomposes according to the following equation
4 C3H5N309 ---> 12 CO2 + 10 H20 + 6 N2 +O2
The moles of CO2 = 25 /44(molar mass of CO2)= 0.568 moles
the mole ratio of C3H5N3O9 to CO2 IS 4:12 from equation above
therefore the moles of C3H5N3O9=( 0.568 x 4)/12= 0.189 moles
mass of C3H5N3O9=moles x molar mass of C3N5N3O9
That is 0.189 mol x 227 g/mol= 42.903 grams