Semester 1 Final Exam (B)

Front

What are coefficients in a chemical equation?

Back

Coefficients are numbers placed in front of the compounds in a chemical equation to indicate the number of molecules or moles of each substance involved in the reaction.

Front

What is the Law of Conservation of Matter?

Back

The Law of Conservation of Matter states that matter cannot be created or destroyed in a chemical reaction; it can only change forms.

Front

What is an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means. Examples include hydrogen and oxygen.

Front

What is a compound?

Back

A compound is a substance formed when two or more elements are chemically bonded together. For example, water (H2O) is a compound made of hydrogen and oxygen.

Front

What is a chemical reaction?

Back

A chemical reaction is a process that leads to the transformation of one set of chemical substances to another, involving the breaking and forming of bonds.

Front

What is the difference between a physical change and a chemical change?

Back

A physical change alters the form of a substance but not its chemical composition (e.g., melting ice), while a chemical change results in the formation of new substances (e.g., rusting iron).

Front

What is frequency in terms of waves?

Back

Frequency is the number of waves that pass a given point in one second, measured in hertz (Hz). Higher frequency means more waves in a given time.

Front

What causes sound?

Back

Sound is caused by vibrations that create pressure waves in a medium, such as air, which our ears detect.

Front

What is an atom?

Back

An atom is the smallest unit of an element that retains the properties of that element, consisting of protons, neutrons, and electrons.

Front

What is a molecule?

Back

A molecule is a group of two or more atoms bonded together, representing the smallest fundamental unit of a chemical compound.