WGU D425 Introduction to Chemistry -PA and OA Actual Exam

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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)

• Atom -

The smallest unit of matter that retains the properties of that matter

• Chemistry –

The study of matter and its interactions

• Elements -

Substances made up of a single type of atom

• Mass –

The measure of the amount of matter that an object contains

• Matter –

A substance that has mass and takes up space (volume)

• Mixture –

Matter composed of two or more pure substances

• Periodic Table -

A chart that displays all the known elements according to the similarities between the elements' properties

• 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) 1 / 4

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• Subatomic Particles –

The components of an atoms

• Volume -

The amount of space a substance or object occupies

• How can matter be divided? –

Pure substances and mixtures

• Chemical Bond –

A force that holds two or more atoms together

• Chemical Formula -

A formula consisting of atomic symbols and subscripts to represent the number and types of atoms within a molecule or a compound

• Chemical Potential Energy -

Energy stores in atoms, molecules, and chemical bonds which make up matter

• 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

• Composition –

The arrangement of molecules and atoms

• Compound – 2 / 4

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A substance made of two or more different elements chemically bonded; have uniform and definite composition (ex - water)

• Crystal Lattice -

Atoms arranged in a specific arrangement in three-dimensional space

• Density –

A physical property found by dividing the mass of an object by its volume

• Diatomic –

A molecule consisting of two atoms (ex - H2, Hydrogen)

• Empirical Formula –

Indicates the types of atoms present and the simplest whole-number ratio of the number of atoms in the compound

• Energy -

The capacity to supply heat or do work

• Extensive Property –

A property that depends on the amount of matter in a sample

• Gas –

A state of matter with no definite volume or shape

• Heat –

The energy flow from an object with higher temperature to an object with lower temperature

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• Heterogeneous Mixture –

Matter that contains two or more different pure substances but is not uniform throughout

• Homogeneous Mixture –

Matter that contains two or more different pure substances and is uniform throughout

• Intensive Property –

A property of matter dependent on the type of matter, not the amount of matter

• Intermolecular Interaction –

The attractive and repulsive force that occurs between molecules in a substance

• Kinetic Energy -

Energy associated with the motion of objects or particles

• 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

• Liquid -

A state of matter with definite volume but no definite shape

• Molecular Formula –

The symbols that represent the total number of atoms of each element in a molecule (a type of chemical formula)

• Molecule –

A group of two or more nonmetal atoms help together by chemical bonds

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