Unit 01: Investigating Elements and Chemical Change

Front

What is a compound?

Back

A compound is a substance formed when two or more elements are chemically bonded together. For example, Carbon Dioxide (CO2) is a compound made of carbon and oxygen.

Front

What is a molecule?

Back

A molecule is the smallest unit of a chemical compound that retains its chemical properties. It consists of two or more atoms bonded together.

Front

What does a chemical formula represent?

Back

A chemical formula represents a compound using the symbols of the elements and subscripts to indicate the number of atoms of each element.

Front

What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. For example, melting ice is a physical change.

Front

What is a subscript in a chemical formula?

Back

A subscript is a number written to the right and slightly below an element symbol in a chemical formula, indicating the number of atoms of that element in the compound.

Front

What is an atom?

Back

An atom is the basic unit of a chemical element, consisting of a nucleus surrounded by electrons.

Front

What is a mixture?

Back

A mixture is a combination of two or more substances where each substance retains its own properties. For example, sand and salt mixed together.

Front

What is a chemical change?

Back

A chemical change is a process that involves the transformation of one or more substances into different substances, often accompanied by energy changes.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance that cannot be broken down into simpler substances, while a compound is made up of two or more elements chemically combined.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; it is conserved.