The standard heat of formation, AH, is defined as the enthalpy change for the formation of one mole of substance from its constituent elements in their standard states. Thus, elements in their standard states have AH = 0. Heat of formation values can be used to calculate the enthalpy change of any reaction. Consider, for example, the reaction 2NO(g) + O₂(g) — 2NO₂ (g) with heat of formation values given by the following table: Substance ΔΗ (kJ/mol) NO(g) 90.2 O₂(g) 0 NO₂(g) 33.2
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.
Pls help ASAP. Pls give proper units and significant digits to three. Pls circle the final answer as well.
![The standard heat of formation, AH, is defined as the
enthalpy change for the formation of one mole of
substance from its constituent elements in their
standard states. Thus, elements in their standard states
have AH = 0. Heat of formation values can be used
to calculate the enthalpy change of any reaction.
Consider, for example, the reaction
2NO(g) + O₂(g) = 2NO₂ (g)
with heat of formation values given by the following
table:
Substance
ΔΗ;
(kJ/mol)
NO(g)
90.2
O₂(g)
0
NO₂(g) 33.2
Then the standard heat of reaction for the overall
reaction is
AHxn AH (products)-
2(33.2)
=
−114 kJ
AH(reactants)
[2(90.2) +0]](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F5974d182-69dd-492b-b0a6-6672f4ac054c%2F510b1d29-39b3-4d31-91ba-c1f47c5e1d88%2F7ty7oz_processed.png&w=3840&q=75)
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 1 images
