Concept explainers
(a)
Interpretation:
Whether the given reaction is endothermic or exothermic needs to be determined.
Concept Introduction :
For a reaction, if heat is required or added then reaction is endothermic and if heat is released then reaction is exothermic.
(b)
Interpretation:
The amount of heat in kcal produced from 5.0 g of ethanol needs to be determined.
Concept Introduction :
The relation between number of moles and mass is as follows:
Here, m is mass and M is molar mass.
(c)
Interpretation:
The mass of ethanol if 1250 kJ of heat is produced needs to be determined.
Concept Introduction :
The relation between number of moles and mass is as follows:
Here, m is mass and M is molar mass.
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