Elements and Compounds 7th Grade

Front

What is an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means. It consists of only one type of atom.

Tags

NGSS.MS-PS1-5

Front

What is a compound?

Back

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

Tags

NGSS.MS-PS1-1

Front

What is the chemical formula for water?

Back

The chemical formula for water is H2O, indicating it is made of two hydrogen atoms and one oxygen atom.

Tags

NGSS.MS-PS1-1

Front

How many atoms are in one molecule of H2O?

Back

There are three atoms in one molecule of H2O: two hydrogen atoms and one oxygen atom.

Tags

NGSS.MS-PS1-1

Front

What is the chemical symbol for Sodium?

Back

The chemical symbol for Sodium is Na.

Front

What is the difference between an element and a compound?

Back

An element is a single type of atom, while a compound consists of two or more different types of atoms chemically bonded together.

Front

What does the subscript in a chemical formula represent?

Back

The subscript in a chemical formula indicates the number of atoms of the element present in the molecule. For example, in H2O, the '2' indicates there are two hydrogen atoms.

Tags

NGSS.MS-PS1-1

Front

What is the chemical symbol for Gold?

Back

The chemical symbol for Gold is Au.

Front

Which of the following is a molecule of a compound: H2, Cl2, H2O, F2?

Back

H2O is a molecule of a compound, as it consists of different elements (hydrogen and oxygen) bonded together.

Tags

NGSS.MS-PS1-1

Front

What is the chemical formula for a compound made of 1 nickel atom and 2 fluorine atoms?

Back

The chemical formula is NiF2.

Tags

NGSS.MS-PS1-1