[noor123]

Calculate the heat released (in kJ) when 1.26*10^4 g of NO2 forms through the following rxn:

2NO2(g)+O2(g)-->2NO2(g)

deltaH=-114.6kJ/mol

I dont really understand how i should start, heat released is same as deltaH(enthalpy) right? so for the given reaction, the enthalpy is as stated, and that is for 2 moles of NO2, and we need it to be for 1.26*10^4 grams,,, so should i just convert the grams into moles, and then multiply by the enthalpy?

[Borek]

should i just convert the grams into moles, and then multiply by the enthalpy?

Close, but if you do it this way, you will be off by a factor of two.