Thermochemistry Webquest worksheet - Quia

ThermoChemistry (Energy) WebQuest
Name _________________________________________ Period _______
Part 1 – Vocabulary http://www.learnchem.net/glossary/
Define the following terms:
1. Kinetic energy –
2. Potential energy –
3. Endothermic –
4. Exothermic –
5. Activation energy –
6. Calorie –
7. Enthalpy -
8. Entropy-
9. Specific Heat Capacity-
10. Free Energy -
11. Hess’s Law –
12. Heat of Fusion-
13. Heat of Vaporization-
14. Heat of Solution-
15. Thermochemical Equation-

ThermoChemistry (Energy) WebQuest
Name _________________________________________ Period _______
Part 2 - Reaction Rates
http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/activa2.swf
Listen to the introduction.
Play & Listen to the Exothermic & Endothermic Reaction animation.
Draw an exothermic & endothermic energy profile
Label: axes, reactants, products, activation energy, activated complex, heat of
reaction
Exothermic
Endothermic
Part 3- Hess’s Law Problems
http://www.youtube.com/watch?v=_NLAgSnqNOE
Watch and Listen to the Hess’s Law Demonstration.
What is the total enthalpy change of the example problem done in the demo?
____________
http://employees.oneonta.edu/viningwj/sims/hess_law_s.html
Click on the Description Button and read the description.
Click and drag the reactions down until the Net Reaction appears as shown below.
Fill in the reactions and H° values below.
Reaction 1:
H°=
Reaction 2:
Reaction 3:
H°=
H°=
Net Reaction: 2SnCl 2 (s) + TiBr 2 (s) + 2Cl 2 (g) SnBr 2 (s) + SnCl 4 (l) +TiCl 4 (l) H° Net =
Change the reactions by clearing and reversing them until the Net Reactions
equals the one shown below. Fill in the reactions and H° values below.

ThermoChemistry (Energy) WebQuest
Name _________________________________________ Period _______
Reaction 1:
Reaction 2:
Reaction 3:
H°=
H°=
H°=
Net Reaction: SnCl 2 (s) + TiBr 2 (s) + Cl 2 (g) SnBr 2 (s) + TiCl 4 (l) H° Net =
Part 4- Specific Heat
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/spht.html#c1
Write the formula that can be used to calculate the heat energy being absorbed or
released in a system.
Describe each part of the equation
Heat gained or lost = Mass x Change in Temperature x Specific Heat
Mass –
Change in temperature -
Specific Heat –
http://employees.oneonta.edu/viningwj/sims/specific_heat_s.html
Click on the Description Button and read the description.
Choose a material from the drop down box. Choose either 5 or 10 grams of your
material. Move the slider to determine how long the material will be heated.
Click HEAT
Fill in the data below and calculate the specific heat of your material.
Initial temp = Final Temp = T =
Mass of Block =
Heat Added to Block =
(show all work)
Specific Heat =

ThermoChemistry (Energy) WebQuest
Name _________________________________________ Period _______
Part 5- Some more Specific Heat Problems
http://www.sciencebugz.com/chemistry/chprbspheat.htm
Show set up for the 3 problems. Calculate the answer and check it.
1. Problem #1
2. Problem #2
3. Problem #3
Part 6 – Mixed Review
calculations done.
Answer the following questions. Show all equations used and
1. Use the thermochemical equations shown below to determine the enthalpy for the reaction:
CH 4 (g) + 2O 2 (g) CO 2 (g) + 2H 2 O(l)
CO 2 (g) C(s) + O 2 (g)
H 2 (g) + ½O 2 (g) H 2 O(l)
CH 4 (g) C(s) + 2H 2 (g)
H=590.2KJ
H=-428.7KJ
H=112.2KJ
2. How much energy must be absorbed by 20.0 g of water to increase its temperature from 283.0°C to
303.0°C?
3. How much heat, in kJ, is given off when 85.0 grams of Pb cools from 225.0°C to 10.0°C?
(Cp of lead = 0.129 J/g°C.)
4. Use the thermochemical equations shown below to determine the enthalpy for the reaction:
COCl 2 (g) + H 2 O(l) CH 2 Cl 2 (l) + O 2 (g)
½H 2 (g) + ½Cl 2 (g) HCl(g)
H 2 O(g) + Cl 2 (g) 2HCl(g) + ½O 2 (g)
CH 2 Cl 2 (l) + H 2 (g) + 3/2O 2 (g) COCl 2 (g) + 2H 2 O(l)
H=-46KJ
H=-21KJ
H=-80.5KJ