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Do Now … May 15, 2017Obj: Define and apply the concept of activation energy.
Copy: Activation energy is the amount of energy needed to initiate (start or begin) a chemical reaction.What is the activation energy used to light a match?
Monday, May 15, 2017
Today: W-Up, Notes & Practice: Activation
Energy
Homework: Complete Practice
Graph of
Rxn Exothermic
Graph of
Rxn Endothermic
Graph of
Rxn Exothermic
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Practice …
Quick Quiz1. List two exothermic chemical reactions.
2. Draw a graph for an endothermic reaction (label reactants, activation energy, and reactants).
3. In an endothermic reaction, where is the energy stored?
Do Now … May 16, 2017Obj: Observe and collect data on endothermic and exothermic reactions.
Copy and do: Define and draw graphs showing an endothermic and exothermic reaction.Which graph shows energy being stored?
Tuesday, May 16, 2017
Today: W-Up, Lab: Endo & Exothermic Reactions
Homework: Finish Lab, Google Form
Graph ofEndothermicRxn
Graph ofExothermicRxn
Graph of
Rxn Exothermic
Do Now …Date: May 17, 2017
Obj: Describe and calculate entropy and enthalpy.Copy and do:Entropy (ΔS) describes the amount disorderin a system.Order the following from least to greatest entropy: liquid, gas, solid
Wednesday, May 17, 2017
Today:
W-Up, Notes & Practice: Entropy & Enthalpy
Homework: Complete Practice
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Do Now … May 18, 2017Obj: Collect data and calculate specific heat.
Copy: Enthalpy (∆H): Change in heat in a system.Entropy (∆S): Change in order/disorder.Gibbs Free Energy (∆G): Tells if a reaction will happen at a given temperature.
PARCC
Do Now …May 19, 2017Obj: Collect data and calculate specific heat.
Copy: Enthalpy (∆H): Change in heat in a system.Entropy (∆S): Change in order/disorder.Gibbs Free Energy (∆G): Tells if a reaction will happen at a given temperature.
PARCC
Do Now … Mon, May 22, 2017Obj: Define and apply the concept of activation energy.
Copy: Activation energy is the amount of energy needed to initiate (start or begin) a chemical reaction.Draw an energy diagram to show the activation energy used to light a match?
PARCC
Do Now … Tues, May 23, 2017Obj: Define and apply the concept of activation energy.
Copy: Activation energy is the amount of energy needed to initiate (start or begin) a chemical reaction.Draw an energy diagram to show the activation energy used to light a match?
PARCC
Wednesday, May 24, 2017
Today: W-Up, Notes: Gibbs Free Energy, PracticeHW: Prepare for Quiz tomorrow.
Energy Changes
Energy changes in a reaction are due mostly to changes in potential energy from breaking chemical bonds (in the reactants) and forming
new bonds (in the products).
Reactants Products
First Law of Thermodynamics
First Law of Thermodynamics states that energy cannot be created or destroyed.
The amount of energy in a system stays the same.
Also called the Law of Conservation of Energy.
First Law of Thermodynamics
System, Surroundings, Universe
Important in how we describe changes.
.
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From http://cwx.prenhall.com/petrucci/medialib/media_portfolio/text_images/FG07_012.JPG
Closed
Open
Closed/Isolated
First Law of Thermodynamics
Describe the system, surroundings, and universe.
- A student heats a test tube over a Bunsen burner.
- My cells produce energy for my body to function.
Enthalpy
Enthalpy is the change in heat of a system.
For example:melting or freezing
or
HCl + NaOH H2O + NaCl
Enthalpy
Enthalpy is the change in heat of a system.
The change in enthalpy is symbolized as ∆H .
∆Hreaction = Σ ∆Hf (products) - Σ ∆Hf (reactants)
∆ = change Σ = sum
Enthalpy
Enthalpy is the change in heat of a system.
The change in enthalpy is symbolized as ∆H .
We look up ∆Hf in chemistry tables.
∆Hreaction = Σ ∆Hf (products) - Σ ∆Hf (reactants)
∆ = change Σ = sum
Enthalpy
Enthalpy is the change in heat of a system. ∆Hreaction = Σ ∆Hf (products) - Σ ∆Hf (reactants)
For example … P4O10 + 6H2O 4H3PO4
∆Hfo for reactant P4O10 = -2980 kJ/mole
∆Hfo for reactant H2O (l) = -286 kJ/mole
∆Hfo for product H3PO4 = -1280 kJ/mole
Calculate ∆Hreaction∆Hro = - 424 kJ
Graph ofEndothermicRxn
Graph ofExothermicRxn
Introduction to Thermodynamics
One your own paper, write down the following terms (leave space b/t terms).
Spontaneous Endothermic, Exothermic Enthalpy
ΔH Reactants, Energy, Products
Write a definition of each and give examples when possible.
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http://en.wikipedia.org/wiki/Image:Candleburning.jpg
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http://en.wikipedia.org/wiki/Image:Candles.jpg
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From http://cwx.prenhall.com/bookbind/pubbooks/hillchem3/medialib/media_portfolio/text_images/CH12/FG12_11.JPG
Exothermic Reaction
Reactants Products + Energy
Heat is released.
ΔH = energy used in bond breaking reactions -energy released in bond making products
So the sign of ΔH is: Negative
Endothermic Reaction
Reactants + Energy Products
Heat is absorbed.
ΔH = energy used in bond breaking reactions -energy released in bond making products
So the sign of ΔH is: Positive
.
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From http://www.playafoot.com/photos/burningman/2005/271_9572.jpg
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From http://cwx.prenhall.com/bookbind/pubbooks/hillchem3/medialib/media_portfolio/06.html
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From http://www.waltercunningham.com/art/flame.jpg
What is ΔH?
Enthalpy (H) is the sum of internal energy.
ΔH is the change in enthalpy.
.
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From http://www.chem.psu.edu/ncs/Halloween%20Show%202003/Thermite.jpg
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From http://www.bananabaymarina.
com/images/volcano.jpg
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From www.cormix.info/faq.php
http://stinc.org/_img/gallery/34.jpg
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From www.cormix.info/faq.php
From http://www.lyonsny.com/images/fireworks/fireworks_05.JPG
Do Now …Date: May 25, 2017
Obj: Use Gibbs Free Energy Equation to predict whether a chem rxn will be spontaneous.
Copy: Given the equation:I2(s) + 64.2 kJ I2(g)
What is the value for ∆ H? For ∆S?
Thursday, May 25, 2017
Today:
W-Up, Notes & Practice, Quiz (longer)
HW:
Fe Colliding with O2
http://www.youtube.com/watch?v=Yvw5epSmH3Q&feature=related
Do Now …Date: May 26, 2017
Obj: Use Gibbs Free Energy Equation to predict whether a chem rxn will be spontaneous.
Copy: Given the equation:I2(s) + 64.2 kJ I2(g)
What is the value for ∆ H? For ∆S?
Friday, May 25, 2017
Today:
W-Up, Lab: Specific Heat of Metals
HW:
----Old Content---
Do Now …Date: May , 2015
Obj: Collect data and calculate specific heat.
Copy: Scientists use theories (explanations based on data) when they approach new problems.What are two advantages of doing so?1.2.
Thursday, May 25, 2015
Today: W-Up, Begin Thermodynamics Project
Molar Heat of Reaction
The molar heat of reaction is defined as the change in enthalpy for the formation of one mole of
a compound from its elements (at standard temperature and pressure).
More Molar Heats of …
The amount of heat absorbed (an endothermic reaction) and the amount of heat liberated (an exothermic reaction) varies with temperature.
Therefore we define standard temperature as 25°C and standard pressure as 1 atm when
reporting heat data.
(This is a different standard temperature than we used for gases.)
Hess’s Law
Hess’s Law states that we can add two or more thermodynamic equations to give a final equation. This allows you to add the heat changes to give a
final heat change.
Efficiency
What do we mean when we say a something is energy efficient ?
List three examples where energy efficiency is important.
What does Energy Star® mean?
Do Now …Date: May 8, 2015
Obj: Use Collision Theory to improve out designs from yesterday.
Copy:In order for two atoms or molecules to react they must collide (bump into each other).How can you increase the number of collisions?
Friday , May 8, 2015
Today:
W-Up, Thermodynamics Project (Collision Theory)
HW: Complete Practice
Fe Colliding with O2
http://www.youtube.com/watch?v=Yvw5epSmH3Q&feature=related
Stop Motion AnimationProof of Concept: a very simple animation of two atoms colliding and making a new molecule.
Stop Motion Animation• Recommended Free App: iMotion• Set to manual to create stop motion.• Use several books to position phone.• Use markers, paper, and scissors to
create atoms. • Have a frame with your names first.• Show me the animation.
