Baking soda is sodium bicarbonate (NaHCO3). When you heat baking soda, it breaks down into sodium carbonate powder (Na2CO3), water vapor, and carbon dioxide. The enthalpy of this reaction is 129 kJ.

Question

a. Write a correct, balanced thermochemical equation for this reaction. (Remember all the parts!)

Answer 1

I'm not exactly sure what you want but I would do this for the balanced chemial equation. For the thermo equation you want this without the 2 coefficient and you want to add the dH = -129 kJ/mol
2NaHCO3 ==> Na2CO3 + CO2 + H2O
NaHCO3 ==> 1/2 Na2CO3 + 1/2 CO2 + 1/2 H2O + 129 kJ or if you prefer
NaHCO3 ==> 1/2 Na2CO3 + etc etc delta H = -129 kJ/mol. I think the latter is more in line with the way a thermodynamicist would want it but I'm not that picky.