hard chemistry problem?

Question

The specific heat of aluminum is .902 J/g Celsius. how much heat is absorbed by an aluminum pie tin with a mass of 473 g to raise its temperature from 23.00 Celsius to 191 Celsius?

Strontium carbonate can be produced by combining strontium metal, graphite (C) and oxygen gas. the formation of one mole of SRCO3 releases 1.220x10^3 kJ of energy
write a balanced thermochemical equation for the reaction,
what is delta H when 10.00 L of oxygen at 25 Celsius and 1.00 atm is used by the reaction?

Answer 1

(473 g)(902 J/g°C)(191° - 23°) =
71,676,528 J ≈ 71.7 MJ

2Sr + 2C + 3O2 → 2SrCO3 + 2.440*10^3 kJ

2(87.62 + 12.01 + 3*16) = 295.26 g SrCO3
3*2*16 = 96 g O2

(10.00 L)(293.15°K/298.15°K)(32 g/22.4 L) ≈
14.04614 g O2
∆H/(2.440*10^3 kJ) = (14.04614 g O2)/(96 g O2)
∆H ≈ 357.0061 kJ ≈ 357 kJ