PRELAB QUESTIONS: 1. How much energy is required to raise 125 grams of water from 22.0 °C to 43.2 °C? The specific heat (S) of water is 1.000 cal/g °C.
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.
![**Prelab Questions:**
1. **How much energy is required to raise 125 grams of water from 22.0 °C to 43.2 °C?** The specific heat (S) of water is 1.000 cal/g °C.
2. **An almond weighs 0.823 grams.** When the almond is burned in a calorimeter that contains 124.2 grams of water, the water temperature changes from 23.5 °C to 45.7 °C. The “uncombusted remains” of the almond weigh 0.615 grams.
a) **Calculate the change in temperature (ΔT) of the water.**
b) **Calculate the amount of energy that was released from the almond sample.**
- Assume that all of the energy released from the almond was transferred to the water. Use the specific heat (S) of water (1.000 cal/g °C), the mass of the water that was in the flask, and the temperature change (ΔT) of the water to calculate the amount of energy (Q) that was transferred to the water, and thus the amount of energy that was released from almond.
c) **Calculate the mass of the almond that was “completely combusted”.** This is done by subtracting the mass of “uncombusted remains” of the almond from the original mass of the almond.
d) **Calculate the energy per gram of almonds** by dividing the energy that was released from the almond (from part b) by the mass of the almond that was “completely combusted” (from part c).](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F7ee6b212-2222-4f62-9688-db3337d285cf%2Fe6ca2c44-48b8-4f2f-890d-1e4f6481c222%2F2wfw45_processed.jpeg&w=3840&q=75)
![](/static/compass_v2/shared-icons/check-mark.png)
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 2 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)