Unit 1: Physical Properties & Changes

Question 1

What is the state of motion in solid?

Answer 1

Vibrate in fixed positions

Question 2

What is the state of motion in liquid

Answer 2

Slide past each other

Question 3

What is the state of motion in Gas

Answer 3

Move freely & rapidly in all direction

Question 4

What type of motion do particles in a solid exhibit?

Answer 4

Vibrate

Particles in solids are tightly packed and do not move freely.

Question 5

In which state of matter are particles tightly packed together?

Answer 5

Solid

This results in a high density.

Question 6

What is the density of solids compared to liquids and gases?

Answer 6

High

Solids have particles that are close together.

Question 7

What is the diffusion rate in solids?

Answer 7

Very slow

Particles in solids do not move freely.

Question 8

What is the state of matter characterized by particles that are far apart and not in fixed positions?

Answer 8

Gas

Gases have the weakest intermolecular forces.

Question 9

What is the nature of physical properties?

Answer 9

Observable with the senses

Physical properties can be determined without destroying the object.

Question 10

What is a physical change?

Answer 10

Change in form/state without changing identity

The substance remains the same despite the change.

Question 11

What defines chemical properties?

Answer 11

Ability to chemically react to form a new substance

Chemical properties describe how a substance interacts with others.

Question 12

What is a chemical change?

Answer 12

Formation of a new substance with new properties

This involves a chemical reaction.

Question 13

Fill in the blank: The ability of a substance to chemically react is known as its _______.

Answer 13

Chemical properties

Chemical properties indicate potential changes in composition.

Question 14

Fill in the blank: A _______ change is a change in form or state without changing the substance’s identity.

Answer 14

Physical

Examples include melting and freezing.

Question 15

What is an allotrope?

Answer 15

Different arrangement of the same element

Allotropes can exhibit different physical and chemical properties despite being composed of the same element.

Question 16

Define amorphous solids.

Answer 16

Irregular arrangement of particles

Amorphous solids lack a defined crystalline structure.

Question 17

What is the Kinetic Molecular Theory?

Answer 17

A theory that describes the behavior of particles in gases

It explains the properties of gases based on the motion of their particles.

Question 18

What assumption does the Kinetic Molecular Theory make about particle volume?

Answer 18

The volume of particles is assumed to be zero

This assumption is valid due to the large distances between particles in a gas.

Question 19

What is stated about the motion of particles in the Kinetic Molecular Theory?

Answer 19

Particles are in constant motion

This constant motion contributes to the properties of gases.

Question 20

What does the Kinetic Molecular Theory say about the forces between particles?

Answer 20

Particles are assumed to exert no forces on each other

This assumption simplifies the analysis of gas behavior.

Question 21

What is the relationship between average kinetic energy and temperature in gases?

Answer 21

Average kinetic energy is proportional to Kelvin temperature

Higher temperatures correlate with higher average kinetic energy of gas molecules.

Question 22

How do intermolecular forces affect solids?

Answer 22

Keep the molecules ordered

Intermolecular forces are crucial in maintaining the structure of solids.

Question 23

What does IMF stand for?

Answer 23

Intermolecular Forces

Question 24

Fill in the blank: The average kinetic energy of gas molecules is assumed to be proportional to its _______.

Answer 24

Kelvin temperature

Question 25

What does IMF mean?

Answer 25

force of attraction or repulsion between molecules

Question 26

What is the strongest type of intermolecular force?

Answer 26

Solid ## Footnote Particles are harder to move in solids due to strong intermolecular forces.

Question 27

What is the weakest type of intermolecular force?

Answer 27

Gas ## Footnote Particles move freely in gases due to weak intermolecular forces.

Question 28

What does endothermic mean?

Answer 28

Energy enters ## Footnote Endothermic processes feel cold to the touch.

Question 29

What does exothermic mean?

Answer 29

Energy exits ## Footnote Exothermic processes feel warm to the touch.

Question 30

What is the definition of intermolecular?

Answer 30

In between molecules ## Footnote Refers to the forces that occur between molecules.

Question 31

What is the process of melting?

Answer 31

Solid → Liquid → particles gain energy ## Footnote Melting occurs when heat is added.

Question 32

What is evaporation?

Answer 32

Liquid → Gas → particles break free ## Footnote Evaporation requires the addition of heat.

Question 33

What happens during condensation?

Answer 33

Gas → Liquid → particles lose energy ## Footnote Condensation requires heat removal.

Question 34

What is freezing?

Answer 34

Liquid → Solid → particles slow down ## Footnote Freezing occurs when heat is removed.

Question 35

What is sublimation?

Answer 35

Solid → Gas → particles skip liquid stage ## Footnote Sublimation occurs when heat is added.

Question 36

What is the definition of intramolecular?

Answer 36

Inside a molecule ## Footnote Refers to the forces that occur within a molecule.

Question 37

What is electronegativity?

Answer 37

How strongly an atom pulls electrons in a bond ## Footnote Electronegativity determines the nature of bonds between atoms.

Question 38

What is deposition?

Answer 38

Gas → Solid → remove heat ## Footnote Deposition occurs when gas turns directly into solid.

Question 39

What is the breaking of intermolecular forces (IMF) associated with?

Answer 39

Melting and boiling points

Question 40

What occurs during melting?

Answer 40

Solid to liquid phase change

Question 41

What is the term for the temperature at which a solid becomes a liquid?

Answer 41

Melting Point

Question 42

What phase change occurs at the boiling point?

Answer 42

Liquid to gas phase change

Question 43

What is the term for the temperature at which a liquid becomes a gas?

Answer 43

Boiling Point

Question 44

What happens to molecules as they gain energy?

Answer 44

Molecules increase in kinetic energy

Question 45

What does a heating curve represent?

Answer 45

The gain of energy and increase in temperature

Question 46

What is indicated by a wider curve on a kinetic energy graph?

Answer 46

More high-energy molecules

Question 47

What does the rate of evaporation depend on?

Answer 47

Kinetic energy of particles

Question 48

Fill in the blank: More area of the _______ line means more particles can evaporate.

Answer 48

IMF

Question 49

True or False: More particles having kinetic energy beyond the IMF line results in fewer molecules breaking free.

Answer 49

False