1.1 The Study of Chemistry

Question 1

What is matter?

Answer 1

Anything that has mass and takes up space.

Question 2

What is a property?

Answer 2

An essential or distinctive characteristic that allows us to recognize a particular type of matter, enabling one to distinguish it from other types.

Question 3

What are the states of matter?

Answer 3

A sample of matter can be a gas, liquid, or solid.

Question 4

Which state of matter has no fixed shape or volume, but rather conforms to the shadow of its container.

Answer 4

Gas.

Question 5

Which state of matter has volume independent of its container, but no specific shape?

Answer 5

Liquid.

Question 6

Which state of matter has distinct volume and shape?

Answer 6

Solid.

Question 7

What is the particle theory of matter?

Answer 7

All matter is made up of tiny particles that have empty space between them.

This theory explains the composition and behavior of matter.

Question 8

What are the characteristics of particles in different substances?

Answer 8

Different substances are made up of different kinds of particles.

This indicates that the properties of substances are determined by the types of particles they contain.

Question 9

What is the state of motion of particles according to the particle theory?

Answer 9

Particles are in constant random motion.

This constant motion is a fundamental aspect of the behavior of matter.

Question 10

How does temperature affect the motion of particles?

Answer 10

The particles of a substance move faster as the temperature increases.

This relationship highlights the effect of thermal energy on particle kinetics.

Question 11

What is the nature of attraction between particles?

Answer 11

Particles attract each other.

This attraction influences the physical properties of substances, such as state and density.

Question 12

What is a pure substance?

Answer 12

A substance that is made up of only one type of particle.

Pure substances have a distinct composition that does not vary sample to sample.

Question 13

Give two examples of pure substances.

Answer 13

Water and table salt (sodium chloride)

These are primary components of seawater.

Question 14

What are the two categories of pure substances?

Answer 14

Compounds and elements.

All pure substances fall into one of these two categories.

Question 15

What is an element?

Answer 15

Pure substances that cannot be broken down into simpler substances.

Examples include Hydrogen, Helium, and Oxygen.

Question 16

What are compounds?

Answer 16

Substances composed of two or more elements that contain two or more atoms.

Compounds differ from elements in that they consist of multiple types of atoms.

Question 17

Fill in the blank: Elements are pure substances that cannot be broken down into _______.

Answer 17

[simpler substances]

Question 18

True or False: Each element is composed of only one kind of atom.

Answer 18

True

Question 19

What distinguishes a compound from an element?

Answer 19

A compound is composed of two or more elements, while an element consists of only one kind of atom.

Question 20

What is the law of constant composition?

Answer 20

The observation that the composition of a compound is always the same.

Question 21

What makes water a compound?

Answer 21

Water is made up of two different elements: Hydrogen and Oxygen.

Question 22

True or False: Hydrogen and Oxygen are compounds.

Answer 22

False

Question 23

Fill in the blank: The composition of a _______ is always the same.

Answer 23

[compound]

Question 24

List the elements that make up a molecule of water.

Answer 24

• Hydrogen
• Oxygen

Question 25

What is a mixture?

Answer 25

A type of substance which is made up of more than one type of particle ## Footnote Example: Adding a pinch of salt to a glass of distilled water.

Question 26

What are heterogeneous mixtures?

Answer 26

Mixtures that do not have the same composition, properties, and appearance throughout ## Footnote Heterogeneous mixtures are made up of more than one phase and can be separated physically.

Question 27

What are the characteristics of heterogeneous mixtures?

Answer 27

* Made up of more than one phase * Components are visibly distinguishable * Can be separated physically

Question 28

What is a homogeneous mixture?

Answer 28

A mixture that has only one phase and consists of a uniform appearance throughout ## Footnote Homogeneous mixtures are also known as solutions.

Question 29

What are the properties of a homogeneous mixture?

Answer 29

* Only one phase * Uniform appearance * Any portion of the sample has the same properties and composition

Question 30

True or False: A homogeneous mixture can have visibly distinguishable components.

Answer 30

False ## Footnote In a homogeneous mixture, each region of the sample is identical to other regions.

Question 31

Fill in the blank: A sample of milk appears to be uniform to the eye, however, it is a _______ mixture.

Answer 31

heterogeneous mixture ## Footnote Microscopic examination reveals its composition of water, proteins, carbohydrates, fats, vitamins, and minerals.

Question 32

What are atoms?

Answer 32

Atoms are the basic building blocks of matter that make up everyday objects ## Footnote There are 90 naturally occurring kinds of atoms, with about 25 more created in labs.

Question 33

What are the three basic particles that make up atoms?

Answer 33

Protons, Neutrons, Electrons ## Footnote Protons carry a positive charge, Neutrons carry no charge, and Electrons carry a negative charge.

Question 34

Where are protons and neutrons located within the atom?

Answer 34

In the nucleus ## Footnote The nucleus is the central part of the atom.

Question 35

Are protons and neutrons the smallest particles within the nucleus?

Answer 35

No ## Footnote Quarks are the smallest particles inside the nucleus.

Question 36

How many quarks are there within each proton and neutron?

Answer 36

Three ## Footnote Quarks combine to form protons and neutrons.

Question 37

What particles hold quarks together?

Answer 37

Gluons ## Footnote Gluons are the particles that hold quarks together within protons and neutrons.

Question 38

Fill in the blank: Atoms are made up of three basic particles: Protons, Neutrons, and _______.

Answer 38

Electrons

Question 39

What are molecules?

Answer 39

Two or more atoms joined together in stuff shapes.

Question 40

What are physical properties?

Answer 40

A change in which the composition of the substance remains unaltered and no new substances are produced. ## Footnote Physical properties can be observed without changing the identity and composition of the substance.

Question 41

List examples of physical properties.

Answer 41

* Color * Odor * Density * Melting point * Boiling point * Hardness ## Footnote These properties give information detailing what the substance is like.

Question 42

What are qualitative properties?

Answer 42

Property of a substance that is not measured (no numerical value) e.g., color and odor. ## Footnote Qualitative properties describe characteristics that can be observed but not quantified.

Question 43

What are quantitative properties?

Answer 43

Property of a substance that is measured (holds numerical value) e.g., density, melting point, and boiling point. ## Footnote Quantitative properties provide measurable and numerical data about a substance.

Question 44

What is a chemical property?

Answer 44

A property of a substance that describes its ability to undergo changes to its composition to produce one or more new substances. ## Footnote It involves a change in the starting substance and the production of new substances.

Question 45

What is a common chemical property?

Answer 45

Flammability, the ability of a substance to burn in the presence of oxygen. ## Footnote Flammability is a characteristic that indicates how a substance reacts with fire.

Question 46

List examples of chemical changes.

Answer 46

* Change in color * Change in odor * Production of bubbles without heating * Formation of a new solid * Change in temperature or light ## Footnote These changes indicate that a chemical reaction has occurred.

Question 47

True or False: In a chemical change, the original substance disappears completely.

Answer 47

False ## Footnote In a chemical change, components of the original substances are rearranged to form new substances.