Grade 8 - Elements, Compound & Mixtures

An element is a pure substance in which there are how many kinds of atoms?

• one kind

• two kinds

• three kinds

• four kinds

Tags

NGSS.MS-PS1-1

When two or more elements join together chemically…

• a compound is formed.

• a mixture is formed.

• a substance that is the same as the elements is formed.

• the physical properties of the substances remain the same.

Tags

NGSS.MS-PS1-2

How do elements join to form compounds?

• randomly

• in a specific mass ratio

• in a ratio of 1 to 8

• as the scientist plans it

Tags

NGSS.MS-PS1-1

How do the properties of a compound compare with the properties of the elements that make up the compound?

• Only the physical properties are the same.

• Only the chemical properties are the same.

• All the properties are identical.

• The properties are different.

By what processes can compounds be broken down?

• physical changes

• chemical changes

• compound changes

• either physical or chemical changes

Tags

NGSS.MS-PS1-2

What kind of pure substance forms when two elements chemically combine?

• an element

• a compound

• a mixture

• a solution

Which of the following is the process in which particles of substances separate and spread evenly throughout a mixture?

• filtration

• dissolving

• concentration

• distillation

Which of the following is true about elements?

• They are impure substances.

• They cannot be classified by their properties alone.

• They cannot be broken down into simpler substances.

• They have more than one kind of particle.

Tags

NGSS.MS-PS1-1

Which of the following is NOT true of compounds?

• They contain two or more elements.

• They form after a physical change.

• They have their own physical properties.

• They do not form randomly.

What can be said about the properties of a compound?

• They are different from the properties of the elements that form

  the compound.

• They are identical to the properties of the elements that form the compound.

• They are not unique.

• They are formed after a physical reaction.

Tags

NGSS.MS-PS1-2