Thermodynamics

Question 1

What is statistical thermodynamics?

Answer 1

The unification of macroscopic and microscopic approaches.

Question 2

What is an open system?

Answer 2

A system that can exchange both matter and energy with its surroundings.

Question 3

What is a closed system?

Answer 3

A system that can exchange energy but not matter with its surroundings.

Question 4

What is an isolated system?

Answer 4

A system that can’t exchange matter nor energy with its surroundings.

Question 5

What is the symbol for heat?

Answer 5

q

Question 6

What is heat?

Answer 6

Energy dispersed as random motion.

Question 7

What is the symbol for work?

Answer 7

w

Question 8

What is work?

Answer 8

Energy dispersed as non-random motion.

Question 9

What is the -1st law?

Answer 9

Heat travels from hot to cold.

Question 10

What is the zero law?

Answer 10

If the bodies A and B and B and C are in thermal equilibrium then A and C are in thermal equilibrium.

Question 11

What is the symbol for internal energy?

Answer 11

U

Question 12

What is internal energy?

Answer 12

The total energy contained within a system.

Question 13

What happens to the system if the internal energy system is less than zero?

Answer 13

Energy is lost from the system.

Question 14

What happens to the system if the internal energy change is greater than zero?

Answer 14

Energy is gained from the system.

Question 15

What is the 1st law of thermodynamics?

Answer 15

The internal energy of an isolated system is constant.

Question 16

What is the symbol for enthalpy?

Answer 16

H

Question 17

What kind of process has occurred if enthalpy is less than zero?

Answer 17

An exothermic process.

Question 18

What kind of process has occurred if the enthalpy is greater than zero?

Answer 18

An endothermic process.

Question 19

What is a spontaneous change?

Answer 19

One that doesn’t require input of energy.

Question 20

What is a non-spontaneous change?

Answer 20

A change that requires work in order to be brought about.

Question 21

What is the symbol for entropy?

Answer 21

S

Question 22

What is the second law of thermodynamics?

Answer 22

The entropy of an isolated system increases for any spontaneous change.

Question 23

What does the thermodynamic equilibrium represent?

Answer 23

The natural tendency for things to fall to a lower energy.

Question 24

What is the third law of thermodynamics?

Answer 24

The entropy of a perfect crystal at absolute zero of the temperature scale is zero.

Question 25

What is standard molar entropy?

Answer 25

The entropy in one mole of a substance under standard conditions.

Question 26

What is standard free energy change?

Answer 26

The value of dG when reactants in their standard states are converted to products in their standard states.

Question 27

What is the free energy of formation?

Answer 27

The free energy change when a compound in its standard sate is prepared from its elements in their standard states.

Question 28

What is the reaction quotient (Q)?

Answer 28

It defines reactants and products concentrations ratio at any stage of the chemical transformation.

Question 29

What is the equilibrium constant?

Answer 29

The value of the reaction quotient at equilibrium.