Posted by Jenna on .
According to the following thermochemical reaction, how much energy is involved in the reaction of 18.5 g of NaHCO3? Is the reaction endothermic or exothermic according to how the thermochemical equation is written?
2NaHCO3(s) + 129 kJ → Na2CO3(s) + H2O(l) + CO2(g)
You have to add heat so endothermic
129 J per 2 mol
1 mol = 23 + 1 + 12 + 48 = 84 grams
2 mol = 168 grams
we only have 18.5 grams so
(18.5/168)129 = 14.2 Joules
oops --Damon--Science -
I think Damon made a typo. That is kJ and not J.
Thanks for catching that !!!