Question (b) and (c) (C) Given that the enthalpy change of formation of [H2O]=-286KJ/mol and the enthalpy change of formation of [CO2] = -390KJ/mol. Calcualte they standard enthalpy of formation of ethane.
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.
Question (b) and (c)
(C) Given that the enthalpy change of formation of [H2O]=-286KJ/mol and the enthalpy change of formation of [CO2] = -390KJ/mol. Calcualte they standard enthalpy of formation of ethane.
![The standard Enthalpies of combustion at 298K of severai alkanes are given in the
following tables:
-1
Alkane
AH"c, 298/KJmol"
Methane
- 890
Ethane
- 1560
Propane
- 2220
Butane
- 2870](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F5fbc2f7e-eaac-4421-812e-5e89b7b746fc%2F5ac9f84a-603a-4efe-b7de-79c3d40efde2%2Fbdc7dje_processed.jpeg&w=3840&q=75)
![On the graph paper below draw a graph of AH c, 298 against molecular weight
(relative molecular mass of alkanes).
Molecular weight
b)
From the graph estimate a value for the standard Enthaipy of combustion pentane.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F5fbc2f7e-eaac-4421-812e-5e89b7b746fc%2F5ac9f84a-603a-4efe-b7de-79c3d40efde2%2Fzgbhmps_processed.jpeg&w=3840&q=75)
![](/static/compass_v2/shared-icons/check-mark.png)
Step by step
Solved in 3 steps with 1 images
![Blurred answer](/static/compass_v2/solution-images/blurred-answer.jpg)
![Chemistry](https://www.bartleby.com/isbn_cover_images/9781305957404/9781305957404_smallCoverImage.gif)
![Chemistry](https://www.bartleby.com/isbn_cover_images/9781259911156/9781259911156_smallCoverImage.gif)
![Principles of Instrumental Analysis](https://www.bartleby.com/isbn_cover_images/9781305577213/9781305577213_smallCoverImage.gif)
![Chemistry](https://www.bartleby.com/isbn_cover_images/9781305957404/9781305957404_smallCoverImage.gif)
![Chemistry](https://www.bartleby.com/isbn_cover_images/9781259911156/9781259911156_smallCoverImage.gif)
![Principles of Instrumental Analysis](https://www.bartleby.com/isbn_cover_images/9781305577213/9781305577213_smallCoverImage.gif)
![Organic Chemistry](https://www.bartleby.com/isbn_cover_images/9780078021558/9780078021558_smallCoverImage.gif)
![Chemistry: Principles and Reactions](https://www.bartleby.com/isbn_cover_images/9781305079373/9781305079373_smallCoverImage.gif)
![Elementary Principles of Chemical Processes, Bind…](https://www.bartleby.com/isbn_cover_images/9781118431221/9781118431221_smallCoverImage.gif)