GC2 Finals Review (T. Mix)

General Chemistry 2

Finals Review

Ms. Michaela Micole Derelo

OLOPSC | Senior High School

Drag and Drop

Endothermic:

Placeholder

Exothermic: ​

Placeholder

Drag these tiles and drop them in the correct blank above

energy absorbed.

energy is released.

Drag and Drop

Endothermic: ​

Placeholder

Exothermic: ​

Placeholder

Drag these tiles and drop them in the correct blank above

positive △H and heat flow (q)

negative △H and heat flow (q)

energy is released

.

system → surrounding

q = -

△ H = -

Exothermic Process

energy is absorbed

.

surroundings → system

q = +

△ H = +

Endothermic Process

Classifying Energy Changes

Multiple Choice

The energy diagram on the right describes which type of energy change?

• Endothermic

• Exothermic

Multiple Select

Which of the following are examples of an exothermic chemical reaction?

Select all that apply.

• photosynthesis

• burning a piece of wood

• freezing water into ice

• chemical bond formation

Multiple Choice

The energy diagram on the right describes which type of energy change?

• Endothermic

• Exothermic

energy of reactants is HIGHER than energy of products

Exothermic Process

energy of reactants is LOWER than energy of products

Endothermic Process

Classifying Energy Changes

Multiple Choice

Endothermic or exothermic?

• This is an endothermic process.

• This is an exothermic process.

Multiple Choice

Heat is released or absorbed?

• Energy is released.

• Energy is absorbed.

Multiple Choice

Endothermic or exothermic?

• This is an endothermic process.

• This is an exothermic process.

Multiple Choice

Heat is released or absorbed?

• Energy is released.

• Energy is absorbed.

Fill in the Blanks

What is the enthalpy change (△H) for this reaction?

(Type ONLY the value with proper unit! ex: 18 cal)

Reorder

Rewrite the equation putting the heat in as a reactant OR product.

• 3NO3 + H2O

• 2HNO3 + NO

• →

• + 138 kJ

1

2

3

4

• 1
• 2
• 3
• 4

Multiple Choice

Which energy diagram describes the given chemical reaction on the right?

​

Energy Diagrams

How do we construct energy diagrams? Draw a diagram or line graph and indicate the following:

• label the X-axis ("progress of reaction")

• label the Y-axis ("energy")

• Reactants (ex: A + B )

• Products (ex: C )

Example Thermochemical Equation:
A + B + heat ---> C

Multiple Select

Given the energy diagram on the right, which is/are the reactant/s?

Select all that apply.

• A

• B

• C

• D

Multiple Select

Given the energy diagram on the right, which is/are the product/s?

Select all that apply.

• A

• B

• C

• D

Multiple Choice

Is the overall reaction as shown on the right exothermic or endothermic?

How do you know?

• Exothermic because the reactants have lower energy than the products.

• Exothermic because the reactants have higher energy than the products.

• Endothermic because the reactants have lower energy than the products.

• Endothermic because the reactants have higher energy than the products.

Drag and Drop

Heat energy always moves from a​

Placeholder

temperature object to a ​

Placeholder

temperature object.

Drag these tiles and drop them in the correct blank above

higher

lower

Multiple Choice

What does the "U" stand for the formula ∆U = Q + W

• Heat

• Work

• Temperature

• Internal Energy

Fill in the Blanks

A 500 J of energy is applied to a gas, if 200J of work is done by the gas.

What is the change of internal energy (△U)?

(Type ONLY the value with proper unit! ex: 18 cal)

Multiple Choice

Q = - 65 kJ

W = - 20 kJ

∆U = - 85 kJ

Which is true about the given values?

• Heat is applied to the system.

• Work is done to the system.

• Work is performed by the system.

• Heat entered the system.

Multiple Choice

Q = + 100 kJ

W = - 65 kJ

∆U = + 36 kJ

Which is NOT TRUE about the given values?

• Heat is applied to the system.

• Work is done by the system.

• 65 kJ of work is performed by the system.

• 100 kJ of heat was withdrawn from the system.

Multiple Select

Which statement supports the First Law of Thermodynamics?

Select all that apply.

• Energy can be converted from one form into another.

• Energy can neither be created nor destroyed. 

• Heat gained by a system raises the system's temperature.

• Heat added and work performed by the system can influence its internal energy.

Multiple Choice

Given the ΔHf​° values..

H₂O_(l) = -285

CO_{2(aq) =} -413

H₂CO_3(aq) = -699

Calculate the enthalpy for the following reaction:

H₂O_(l) + CO_{2 (aq) ----------->} H₂CO_{3 (aq)}

• -1 kJ

• 1397 kJ

• -1397 kJ

• 2235 kJ

Multiple Choice

Given the ΔHf​° values..

C₂H₄ = 52

O_{2 =} 0

H₂O = -241

CO₂ = -393

Calculate the enthalpy of the reaction.

C₂H_{4 (g)} + 3O_{2 (g) ------->} 2H₂O_(g) + 2CO_{2 (g)}

• -1322

• -1200

• -3213

• 1382