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WGU D425 Introduction to Chemistry -PA and OA Actual Exam
With 300 Questions and Answers Latest 2025/2025 Study Guide
(Complete Solution)
1. Atom -
The smallest unit of matter that retains the properties of that matter
2. Chemistry –
The study of matter and its interactions
3. Elements -
Substances made up of a single type of atom
4. Mass –
The measure of the amount of matter that an object contains
5. Matter –
A substance that has mass and takes up space (volume)
6. Mixture –
Matter composed of two or more pure substances
7. Periodic Table -
A chart that displays all the known elements according to the similarities between the
elements' properties
8. Pure Substance (substance) –
Has a constant composition (meaning that it is the same everywhere) and is made of a
single element or compound (ex - aluminum soda can)
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9. Subatomic Particles –
The components of an atoms
10. Volume -
The amount of space a substance or object occupies
11. How can matter be divided? –
Pure substances and mixtures
12. Chemical Bond –
A force that holds two or more atoms together
13. Chemical Formula -
A formula consisting of atomic symbols and subscripts to represent the number and types
of atoms within a molecule or a compound
14. Chemical Potential Energy -
Energy stores in atoms, molecules, and chemical bonds which make up matter
15. Chemical Property -
Describes the ability of a substance to undergo a specific chemical change and always
produce one or more types of matter that differ from the matter present before the change
16. Composition –
The arrangement of molecules and atoms
17. Compound –
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A substance made of two or more different elements chemically bonded; have uniform and
definite composition (ex - water)
18. Crystal Lattice -
Atoms arranged in a specific arrangement in three-dimensional space
19. Density –
A physical property found by dividing the mass of an object by its volume
20. Diatomic –
A molecule consisting of two atoms (ex - H2, Hydrogen)
21. Empirical Formula –
Indicates the types of atoms present and the simplest whole-number ratio of the number of
atoms in the compound
22. Energy -
The capacity to supply heat or do work
23. Extensive Property –
A property that depends on the amount of matter in a sample
24. Gas –
A state of matter with no definite volume or shape
25. Heat –
The energy flow from an object with higher temperature to an object with lower
temperature
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26. Heterogeneous Mixture –
Matter that contains two or more different pure substances but is not uniform throughout
27. Homogeneous Mixture –
Matter that contains two or more different pure substances and is uniform throughout
28. Intensive Property –
A property of matter dependent on the type of matter, not the amount of matter
29. Intermolecular Interaction –
The attractive and repulsive force that occurs between molecules in a substance
30. Kinetic Energy -
Energy associated with the motion of objects or particles
31. Law of Conservation of Energy –
States that energy can be transformed from one form to another, but the total energy of a
system remains the same
32. Liquid -
A state of matter with definite volume but no definite shape
33. Molecular Formula –
The symbols that represent the total number of atoms of each element in a molecule (a
type of chemical formula)
34. Molecule –
A group of two or more nonmetal atoms help together by chemical bonds
WGU D425 Introduction to Chemistry -PA and OA Actual Exam
With 300 Questions and Answers Latest 2025/2025 Study Guide
(Complete Solution)
1. Atom -
The smallest unit of matter that retains the properties of that matter
2. Chemistry –
The study of matter and its interactions
3. Elements -
Substances made up of a single type of atom
4. Mass –
The measure of the amount of matter that an object contains
5. Matter –
A substance that has mass and takes up space (volume)
6. Mixture –
Matter composed of two or more pure substances
7. Periodic Table -
A chart that displays all the known elements according to the similarities between the
elements' properties
8. Pure Substance (substance) –
Has a constant composition (meaning that it is the same everywhere) and is made of a
single element or compound (ex - aluminum soda can)
, Page 2 of 37
9. Subatomic Particles –
The components of an atoms
10. Volume -
The amount of space a substance or object occupies
11. How can matter be divided? –
Pure substances and mixtures
12. Chemical Bond –
A force that holds two or more atoms together
13. Chemical Formula -
A formula consisting of atomic symbols and subscripts to represent the number and types
of atoms within a molecule or a compound
14. Chemical Potential Energy -
Energy stores in atoms, molecules, and chemical bonds which make up matter
15. Chemical Property -
Describes the ability of a substance to undergo a specific chemical change and always
produce one or more types of matter that differ from the matter present before the change
16. Composition –
The arrangement of molecules and atoms
17. Compound –
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A substance made of two or more different elements chemically bonded; have uniform and
definite composition (ex - water)
18. Crystal Lattice -
Atoms arranged in a specific arrangement in three-dimensional space
19. Density –
A physical property found by dividing the mass of an object by its volume
20. Diatomic –
A molecule consisting of two atoms (ex - H2, Hydrogen)
21. Empirical Formula –
Indicates the types of atoms present and the simplest whole-number ratio of the number of
atoms in the compound
22. Energy -
The capacity to supply heat or do work
23. Extensive Property –
A property that depends on the amount of matter in a sample
24. Gas –
A state of matter with no definite volume or shape
25. Heat –
The energy flow from an object with higher temperature to an object with lower
temperature
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26. Heterogeneous Mixture –
Matter that contains two or more different pure substances but is not uniform throughout
27. Homogeneous Mixture –
Matter that contains two or more different pure substances and is uniform throughout
28. Intensive Property –
A property of matter dependent on the type of matter, not the amount of matter
29. Intermolecular Interaction –
The attractive and repulsive force that occurs between molecules in a substance
30. Kinetic Energy -
Energy associated with the motion of objects or particles
31. Law of Conservation of Energy –
States that energy can be transformed from one form to another, but the total energy of a
system remains the same
32. Liquid -
A state of matter with definite volume but no definite shape
33. Molecular Formula –
The symbols that represent the total number of atoms of each element in a molecule (a
type of chemical formula)
34. Molecule –
A group of two or more nonmetal atoms help together by chemical bonds
