Ch. 6 - Thermodynamics

Specific Heat Capacity (Intro Video - 9:49)

https://www.youtube.com/watch?v=5we65e7EOcg&t=313s

Heat Transfer Simulation

https://energy.concord.org/energy2d/

PHET Heat Transfer

https://phet.colorado.edu/en/simulation/energy-forms-and-changes

Specific Heat Capacities

https://www.engineersedge.com/materials/specific_heat_capacity_of_metals_13259.htm

Brass fastener - brass (yellow)

Paperclip - steel (mild)

*Calculate the Q-value of each metal. Provide example calculations for both pieces of metal.

Hess's Law Video Notes - Guaranteed Collection (10 pts)

https://www.youtube.com/watch?v=Idv2C8HBbug

1. What is the main idea behind Hess's Law?

2. Consider when a reaction has its coefficients multiplied by 2. What is the effect on the enthalpy change for the reaction?

3. Consider when a reaction has its coefficients divided by 2. What is the effect on the enthalpy change for the reaction?

4. Consider if a reaction has its reactants and products trade places (aka reversing the reaction). What is the effect on the enthalpy change for the reaction?

*Watch as many examples as you need to until you get a grasp on the idea behind how Hess's law applies to a system of chemical equations.

For #'s 5 and 6: The only work that you are required to show is what you did to each equation (e.g. multiplied by 3, reversing/flipping, etc.).

5. Determine the enthalpy change of CS₂(ℓ) + 3O₂(g) ---> CO₂(g) + 2SO₂(g) by using the reactions below. Round your answer to one decimal place. The only work that you are required to show is what you did to each equation (e.g. mutliplied by 3, reversing/flipping, etc.)

Eq'n #1: C(s) + O₂(g) ---> CO₂(g) ΔH = −393.5 kJ

Eq'n #2: S(s) + O₂(g) ---> SO₂(g) ΔH = −296.8 kJ

Eq'n #3: C(s) + 2S(s) ---> CS₂(ℓ) ΔH = +87.9 kJ

6. Given the following data:

Eq'n #1: SrO(s) + CO₂(g) ---> SrCO₃(s) ΔH = −234 kJ

Eq'n #2: 2SrO(s) ---> 2Sr(s) + O₂(g) ΔH = +1,184 kJ

Eq'n #3: 2SrCO₃(s) ---> 2Sr(s) + 2C(s, gr) + 3O₂(g) ΔH = +2,440. kJ

Find the ΔH of the following reaction. Round your answer to the ones place.

C(s, gr) + O₂(g) ---> CO₂(g)

Gummy Bear Rocket (Mythbusters Video, 3:42)

https://www.youtube.com/watch?v=fXf9-2JM7lM