Concepts In Chemistry - Physical Chemistry

Question 1

What is thermodynamics?

Answer 1

The study of heat and temperature and their relation to energy and work.

Question 2

What is a system in thermodynamics?

Answer 2

The part of the universe we are interested in studying.

Question 3

What are surroundings in thermodynamics?

Answer 3

The rest of the universe outside the system.

Question 4

What is an isolated system?

Answer 4

No exchange of energy or matter with the surroundings.

Question 5

What is an open system?

Answer 5

Freely exchanges energy and matter with the surroundings.

Question 6

What is a closed system?

Answer 6

Exchanges only energy with the surroundings, not matter.

Question 7

List the four quantities expressed in thermodynamics.

Answer 7

• Temperature (T)
• Internal Energy (U or E)
• Entropy (S)
• Heat (Q)

Question 8

Define extensive properties.

Answer 8

Properties that depend on the amount of matter present in a system.

Question 9

Define intensive properties.

Answer 9

Properties that do not depend on the amount of matter present.

Question 10

What is a state function?

Answer 10

A property that depends only on the current state of the system.

Question 11

What is a path function?

Answer 11

A property that depends on the path by which the system achieved a particular state.

Question 12

What does the Zeroth Law of Thermodynamics state?

Answer 12

If object A is in thermal equilibrium with object C, and object B is in thermal equilibrium with object C, then A and B are in thermal equilibrium.

Question 13

What is heat in thermodynamics?

Answer 13

The process of energy transfer due to thermal contact.

Question 14

What is the formula for internal energy change in terms of heat?

Answer 14

ΔU = q

Question 15

What is an exothermic process?

Answer 15

A process that releases heat into the surroundings.

Question 16

What is an endothermic process?

Answer 16

A process that absorbs heat from the surroundings.

Question 17

What is heat capacity?

Answer 17

The ratio of the heat supplied to the rise in temperature observed.

Question 18

What does the Ideal Gas Law describe?

Answer 18

The relationship between pressure, volume, temperature, and the amount of gas.

Question 19

What is the formula for the Ideal Gas Law?

Answer 19

PV = nRT

Question 20

What is work in thermodynamics?

Answer 20

The energy transferred by the system to its surroundings.

Question 21

What is the formula for the first law of thermodynamics?

Answer 21

ΔU = Q + W

Question 22

What is specific heat?

Answer 22

The energy required to increase the temperature of 1 unit of a substance by 1 degree.

Question 23

True or False: Internal energy is independent of the path taken to reach that state.

Answer 23

True

Question 24

Fill in the blank: The energy transferred as heat is labeled ______.

Answer 24

q

Question 25

What is the formula for the change in internal energy (ΔU) related to heat (Q) and work (W)?

Answer 25

ΔU = Q + W or ΔU = Q − W

Question 26

What does the equation ΔU = Q + W assume about work (W)?

Answer 26

W represents the work done on the system

Question 27

What does the equation ΔU = Q − W assume about work (W)?

Answer 27

W represents the work done by the system

Question 28

True or False: The equations ΔU = Q + W and ΔU = Q − W are equivalent.

Answer 28

True

Question 29

When work is done on a system, how does it affect the internal energy of the system?

Answer 29

It adds to the internal energy of the system

Question 30

When work is done by a system, how does it affect the internal energy of the system?

Answer 30

It takes away from the internal energy of the system

Question 31

Define work (W).

Answer 31

Work is motion against an opposing force

Question 32

Define heat (Q).

Answer 32

Heat is the energy transferred as a result of a temperature difference

Question 33

Define energy (U).

Answer 33

The energy of a system is its capacity to do work

Question 34

What symbols are used to signify 'change in'?

Answer 34

d and Δ

Question 35

What does ΔV represent?

Answer 35

Change in volume

Question 36

Fill in the blank: Work done on a system is represented by _______.

Answer 36

W on gas

Question 37

Fill in the blank: Work done by a system is represented by _______.

Answer 37

W by gas

Question 38

In which textbook can you find more information on energy and chemistry?

Answer 38

Atkins’ Physical Chemistry

Question 39

What is the significance of keeping track of the signs of Q and W?

Answer 39

It is vital for applying the first law of thermodynamics correctly