Question 1

Which is a pure substance?
A)compound
B)mixture
C)solution
D)both B and C

Accepted Answer

A compound is a pure substance made up of two or more elements chemically combined in a fixed ratio. Mixtures (B) and solutions (C) are not pure substances because they are made up of two or more substances that are physically combined and can be separated by physical means.

Question 2

Which has both a definite shape and a definite volume?
A)solid
B)vapor
C)gas
D)liquid

Accepted Answer

Solids have a definite shape and a definite volume, meaning they maintain their shape and volume even if the container they are in is altered.

Question 3

Which phase of matter contains the least force of attraction between particles?
A)solid
B)gas
C)crystal
D)liquid

Accepted Answer

Gas particles have the least force of attraction between them compared to the other phases of matter. This is because they have the highest kinetic energy and are constantly moving and colliding, causing their attraction to be minimal.

Question 4

Why study chemistry?
A)To help inform us about our world
B)To be better able to make informed decisions
C)To help us learn a technique for identifying and solving problems
D)All the above

Accepted Answer

Studying chemistry can inform us about the world around us, such as the composition of materials and the behavior of different substances. This information can help inform our decisions, such as choosing safe products or understanding environmental issues. Additionally, learning chemistry involves problem-solving skills that can be applied to many other areas of life.

Question 5

Which phase of matter contains the greatest force of attraction between particles?
A)solid
B)vapor
C)liquid
D)gas

Accepted Answer

The particles in a solid are closely packed together and have the least amount of kinetic energy. This results in a strong force of attraction between the particles, which is why solids have a fixed shape and volume. In comparison, liquids and gases have weaker forces of attraction as their particles have more kinetic energy and can move more freely. Vapors are gases at or below their boiling point and therefore have the same level of attraction as gases.

Question 6

In which phase of matter are the particles furthest apart?
A)gas
B)solid
C)liquid
D)crystal

Accepted Answer

In a gas, the particles have enough energy to move freely and occupy the entire space available to them. This means that the particles are furthest apart from each other compared to the other phases of matter.

Question 7

Which phase of matter can be compressed or expanded to the greatest degree?
A)solid
B)gas
C)crystal
D)liquid

Accepted Answer

Gases can be compressed or expanded to the greatest degree compared to solids, crystals, and liquids because the particles in a gas are far apart and move freely, allowing for significant changes in volume under pressure or temperature changes.

Question 8

Which is an observation?
A)Atoms consist of protons,neutrons,and electrons.
B)All matter is composed of atoms.
C)Water is colorless.
D)Atoms can form chemical bonds by sharing electrons.

Accepted Answer

An observation is a statement based on what is seen, heard, smelled, tasted or touched. Choice C is an observation because it describes a physical property of water that can be observed with the naked eye. Choices A, B, and D are statements of scientific theory or knowledge, but not observations.

Question 9

A simple statement of natural phenomena to which no exceptions are known under given conditions is a(n)
A)theory
B)observation
C)model
D)scientific law

Accepted Answer

A scientific law is a statement that has been repeatedly tested and found to always be true in a certain set of conditions. It describes a natural phenomenon with no known exceptions.

Question 10

The statement,"An apple a day keeps the doctor away",is best described as a(n)
A)observation
B)law
C)theory
D)hypothesis

Accepted Answer

The statement is a hypothesis because it is a proposed explanation or idea that suggests eating an apple daily can lead to better health and fewer doctor visits, but it is not scientifically proven as a law or theory.

Question 11

Which state of matter consists of particles in regular,repeating,three dimensional geometrical patterns?
A)liquid
B)vapor
C)solid
D)gas

Accepted Answer

Solids have particles that are tightly packed together in a fixed position and have a regular, repeating, three-dimensional geometrical pattern or crystal structure. Liquids have particles that flow and move around each other but don't have a fixed shape or arrangement, while gases have particles that are widely spaced out and move around freely, and vapors refer to the gaseous state of substances that are normally in a solid or liquid state at room temperature and pressure.

Question 12

Which state of matter consists of particles held together firmly but not rigidly? These particles are held together by strong attractive forces,are in close contact with one another,
But are able to flow by one another.
A)gas
B)liquid
C)solid
D)vapor

Accepted Answer

The description given matches the properties of a liquid. Liquids have strong intermolecular forces that hold their particles close together, but these forces are not strong enough to prevent the particles from moving past one another, allowing liquids to flow. Gases have much weaker intermolecular forces and are able to expand to fill a container, while solids have rigid structures that prevent them from flowing freely. Vapor is not a state of matter but rather a term used to describe a gas formed by the evaporation or sublimation of a liquid or solid.

Question 13

The science of chemistry may involve:
A)observation
B)hypothesis development
C)experimentation
D)all the above

Accepted Answer

The science of chemistry involves all three activities - observation, hypothesis development, and experimentation. Observations are made to gather data, hypotheses are developed to explain the data, and experiments are conducted to test the validity of the hypothesis. Therefore, all the above options are correct.

Question 14

Which has neither a definite shape nor a definite volume?
A)crystal
B)solid
C)gas
D)liquid

Accepted Answer

A gas does not have a definite shape or volume. It will fill the entire container it is placed in and take on the shape of that container.

Question 15

A well established hypothesis is often called a(n)
A)observation
B)fact
C)theory
D)law

Accepted Answer

A well established hypothesis is often called a theory. A hypothesis becomes a theory if it is supported through multiple experiments and observations.

Question 16

The statement,"An atom consists of a dense nucleus surrounded by a cloud of electrons", is best described as a(n)
A)theory
B)law
C)hypothesis
D)observation

Accepted Answer

The statement describes the Bohr Model of the atom, which is a theory that explains the structure of atoms. The model proposes that electrons move in specific energy levels around a nucleus made up of protons and neutrons. However, this model was later modified with the discovery of electron orbitals and quantum mechanics.

Question 17

Which is composed of particles with enough energy to completely overcome the attractive forces between them?
A)solid
B)gas
C)liquid
D)crystal

Accepted Answer

A gas is composed of particles with enough energy to completely overcome the attractive forces between them. This means that the particles are free to move around and have a high level of kinetic energy. In contrast, solids and liquids have particles that are held together by strong forces of attraction and do not have as much freedom of movement. A crystal is a type of solid, so it also has particles that are held together by strong forces of attraction.

Question 18

Which is a scientific observation?
A)Freezing and boiling are called physical changes
B)Water freezes at zero degrees C
C)If a substance has a density of 1.00g/mL it must be water.
D)When a substance freezes its molecules lose potential energy.

Accepted Answer

The statement "Water freezes at zero degrees C" is a specific observation of the behavior of water at a particular temperature. The other statements either classify phenomena (A), make generalizations (C), or describe a concept (D), but they do not provide a specific observation.

Question 19

Which has a definite volume but no definite shape?
A)vapor
B)gas
C)solid
D)liquid

Accepted Answer

Liquids have a definite volume because they have a fixed amount of molecules, but they do not have a definite shape because they can take the shape of their container.

Question 20

A tentative explanation of certain facts that provides the basis for further experimentation is a(n)
A)observation
B)hypothesis
C)theory
D)law

Accepted Answer

A hypothesis is a tentative explanation of certain facts that provides the basis for further experimentation.

Quiz 1: An Introduction to Chemistry

Which is a pure substance?

Which has both a definite shape and a definite volume?

Which phase of matter contains the least force of attraction between particles?

Why study chemistry?

Which phase of matter contains the greatest force of attraction between particles?

In which phase of matter are the particles furthest apart?

Which phase of matter can be compressed or expanded to the greatest degree?

Which is an observation?

A simple statement of natural phenomena to which no exceptions are known under given conditions is a(n)

The statement,"An apple a day keeps the doctor away",is best described as a(n)

Which state of matter consists of particles in regular,repeating,three dimensional geometrical patterns?

Which state of matter consists of particles held together firmly but not rigidly? These particles are held together by strong attractive forces,are in close contact with one another, But are able to flow by one another.

The science of chemistry may involve:

Which has neither a definite shape nor a definite volume?

A well established hypothesis is often called a(n)

The statement,"An atom consists of a dense nucleus surrounded by a cloud of electrons", is best described as a(n)

Which is composed of particles with enough energy to completely overcome the attractive forces between them?

Which is a scientific observation?

Which has a definite volume but no definite shape?

A tentative explanation of certain facts that provides the basis for further experimentation is a(n)