00:01
The combustion reaction is provided for methanol, where two moles of ch3oh reacts with three moles of oxygen to produce two moles of carbon dioxide and four moles of water.
00:22
And the delta h for this process is provided as negative 715 kilojoules for the reaction as written, where two moles of methanol are reacting.
00:38
So is it endothermic or exothermic? because we have a negative delta h value, then it is exothermic.
00:47
If it were a positive delta h value, it would be endothermic.
00:51
To determine the amount of energy that is released, because it's negative it's released, when 98 .3 grams of methanol combust, we need to first convert those grams methanol into moles methanol using the molar mass of methanol, which will be the mass of one mole carbon, four moles hydrogen, and one mole oxygen, 32 .04 grams for every one mole.
01:30
And then we see from the balanced chemical reaction that two moles methanol ch3oh release 715 kilojoules...