Thermochemistry

Question 1

What is enthalpy?

Answer 1

Enthalpy is POTENTIAL energy that is released or gained by the chemicals in a reaction.

Question 2

Formation and decomposition reactions are __________ of each other and involve ___________ of compound.

Answer 2

1. Opposite
2. 1 MOLE!

Question 3

Enthalpy Change formation = negative enthalpy change __________

Answer 3

Decomposition

Question 4

Moles (enthalpy change) MOLAR ENTHALPY = _________________

Answer 4

Enthalpy change total

Question 5

Define exothermic:

Answer 5

Exothermic is when the CHEMICAL REACTION releases energy to the environment.

Question 6

Define endothermic:

Answer 6

Endothermic is when the CHEMICAL REACTION absorbs energy from the environment.

Question 7

In an exothermic reaction, the enthalpy change is _____________ and a ______________.

Answer 7

1. Negative
2. Product

Question 8

In an endothermic reaction, the enthalpy change is ____________ and a ____________.

Answer 8

1. Positive
2. Reactant

Question 9

What are the four ways to express the enthalpy of a reaction?

Answer 9

1. Beside a balanced equation as total enthalpy change
2. Beside a balanced equation as molar enthalpy change
3. Within the balanced equation
4. As an energy level diagram

Question 10

The Y-axis of an energy level diagram is the ___________.

Answer 10

Potential energy

Question 11

What is the main difference between cellular respiration and combustion of glucose?

Answer 11

Cellular respiration is in a closed system.
Combustion of glucose is in an open system.