CHEMISTRY (Please write the complete solution legibly. Choose the correct answer. No long explanation needed. Answer in 2 decimal places. Box the final answer.) Calculate ΔE and determine whether the following processes are endothermic or exothermic: a) A balloon is heated by adding 240 J of heat. It expands, doing 135 J of work on the atmosphere. b) A 50 g iron sample is cooled from 100 degrees to 90 degrees, thereby losing approximately 225 J of heat.
Thermochemistry
Thermochemistry can be considered as a branch of thermodynamics that deals with the connections between warmth, work, and various types of energy, formed because of different synthetic and actual cycles. Thermochemistry describes the energy changes that occur as a result of reactions or chemical changes in a substance.
Exergonic Reaction
The term exergonic is derived from the Greek word in which ‘ergon’ means work and exergonic means ‘work outside’. Exergonic reactions releases work energy. Exergonic reactions are different from exothermic reactions, the one that releases only heat energy during the course of the reaction. So, exothermic reaction is one type of exergonic reaction. Exergonic reaction releases work energy in different forms like heat, light or sound. For example, a glow stick releases light making that an exergonic reaction and not an exothermic reaction since no heat is released. Even endothermic reactions at very high temperature are exergonic.
CHEMISTRY (Please write the complete solution legibly. Choose the correct answer. No long explanation needed. Answer in 2 decimal places. Box the final answer.)
Calculate ΔE and determine whether the following processes are endothermic or exothermic:
a) A balloon is heated by adding 240 J of heat. It expands, doing 135 J of work on the atmosphere.
b) A 50 g iron sample is cooled from 100 degrees to 90 degrees, thereby losing approximately 225 J of heat.
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