Answer:
2300 kg of methane will need to be combusted.
Step-by-step explanation:
The enthalpy of this combustion is -882 kJ/mol CH4.
To generate 126799 kJ of energy, we need
![molCH_4=(126799kJ)/(882kJ/mol)= 143.76molCH_4](https://img.qammunity.org/2020/formulas/chemistry/college/moz5bn0imfhvn6viryesaqipsi78nrd6vf.png)
The molecular weight of CH4 is (12+4*1)=16 g/mol
Then, the mass needed to generate 126799 kJ of energy is
![kgCH_4=143.76mol*16(g)/(mol)*(1kg)/(1000g) =2300kgCH_4](https://img.qammunity.org/2020/formulas/chemistry/college/wcb912kl6gkirveubjr2i6ggfgg8poovxt.png)