Measuring energy chgs
Specific Heat
Hess's Law
Enthalpy changes
Bond energies
100

The measure of the average kinetic energy of particles.

What is Temperature?

100

The specific heat of Gold when the temperature of 2.00 grams is raised by 11.7OC and 3.00 J of energy is applied.

What is 0.128 J/gOC ?

100
Statement that describes Hess's Law.

What is the enthalpy change accompanying a chemical reaction is independent of the pathway between the initial and final states?

100

These enthalpy (energy) changes occur when chemical bonds are formed and broken.

What is energy is released when bonds are formed and absorbed when they are broken?

100

The enthalpy change for this reaction: 

2HF --> H2 + F2

Bond energies are as follows: H-H: 430                                                             F-F: 155                                                              H-F: 565

What is +545 kJ?

200

Type of reaction where heat energy transferred from a system (chemical reaction) to the surroundings – the surroundings get hotter.

What is an Exothermic reaction?

200

The specific heat of Silver when 100.0 grams is raised by 2.12 OC, using 50.0 J of energy. 

What is 0.236 J/gOC ?

200

The enthalpy change for the reaction below:

2CO (g) + O2 (g) --> 2CO2 (g)

Rxn 1: 2C(s) + O2(g) -->2CO (g)      -222 kJ/mol

Rxn 2: C(s) + O2(g) --> CO2(g)        -394 kJ/mol

What is -566 kJ/mol?

200

Needed to calculate the heat absorbed by a sample.

I - mass of the sample

II - density of the sample

III - specific heat capacity of the sample

What is I and III only?

200

The enthalpy change for the reaction of ethyne and hydrogen.

C2H2(g) + 2H2(g) --> C2H6(g)

Use information from table 10 of data booklet.

What is -287 kJ/mol?

300

The form of energy that flows from something at a higher temperature to something at a lower temperature.

What is Heat?

300

The enthalpy change of the burning of 1 mole of hexane when the following situation occurs:

1.20 grams of hexane (C6H14) is burnt using 250.0 grams of water raised by 56.0OC. (specific heat of water is 4.18 J/gOC ). 

What is -4200 kJ/mol ?

300

The enthalpy change of the following reaction.

MnO2(s) + C(s) --> Mn(s) + CO2(g)

Rxn 1: C(s) + O2(g) --> CO2(g)          -390 kJ/mol

Rxn 1: Mn(s) + O2(g) --> MnO2(s)      -520 kJ/mol

What is +130 kJ/mol?

300

The correct statement about the energies of this reaction: 

Ba(OH)2(s) + 2NH4SCN(s) --> Ba(SCN)2(aq) + 2NH3(g) + 2H2O(l)

What is the reaction is endothermic and the change in enthalpy is positive?

300

The trend in the bond enthalpies of the C-Cl, C-Br, and C-I bonds.

What is C-Cl> C-Br> C-I becoming weaker due to halogen size/radius increasing/bonding electrons further away from the nucleus/bonds becoming longer?

400

What type of reaction occurs when a system (chemical reaction) takes in heat energy from the surroundings – the surroundings get cooler?

What is an Endothermic reaction?
400
The enthalpy change when 1 mole of octane is burnt, using the following situation:


2.00 kg of octane (C8H18) burnt when the temperature of 500 kg of water is raised by 46.0OC. (specific heat of water = 4.18 J/gOC )

What is -5490 KJ/mol?

400

The enthalpy change of the following equation.

2S(s) + 3O2(g) --> 2SO3(g)

Rxn 1: S(s) + O2(g) --> SO2(g)               -300 kJ

Rxn 2: 2SO2(g) + O2(g) --> 2SO3(g)       -200 kJ

What is -800 kJ?

400

Relationship between products and reactants focusing on stability in an endothermic reaction.

What is reactants are more stable than products and the enthalpy change is positive?

400
The difference between bond-breaking and bond-making relating to which requires energy and which releases energy. Also state which is endothermic and which is exothermic (which positive and which negative).

What is bond-breaking requiring energy (endo) and enthalpy change is positive - and - bond-making releases energy (exo) and enthalpy change is negative.

500

Explanation of why the changes in enthalpy of exothermic and endothermic reactions are either negative or positive.

Exothermic reactions have negative changes in enthalpy because heat is going out - making bonds.

Endothermic reactions have positive changes in enthalpy because heat is being absorbed inward - breaking bonds. 

500

#1 - The enthalpy change of the combustion of      propan-1-ol (C3H7OH):                                 mass of water - 200.00 grams                     change in temperature - 20.4OC                      initial mass - 185.51 grams                             final mass - 184.56 grams.                                #2 - Account for difference between your calculated value and the actual value of -2010 kJ/mol.


What is -1080 kJ/mol?

What is heat energy loss to the surroundings, or incomplete combustion? (or evaporation of water or propan-1-ol)?

500

The definition of average bond enthalpy.

What is the energy required to break (a mole of) bonds in the gaseous state/ energy given out when (a mole of ) bonds are made in the gaseous state or average value from a number of similar compounds?

500

CH4 + H2O --> 3H2 + CO                   +210 kJ

The energy change that occurs when 1 mol of hydrogen is formed in the reaction above.

What is 70 kJ of energy are absorbed from the surroundings?

500

The reason that all bond enthalpies are positive values.

What is bond enthalpies are defined in terms of breaking bonds and therefore, have positive values due to being endothermic and requiring energy?

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