Elements, Compounds and Mixtures

The chart below lists some substances and their symbols. How many of these substances are examples of elements?

• 1

• 2

• 3

• 4

What makes elements and compounds different from mixtures? Elements & compounds-

• have a constant composition (pure substances)

• are made of gases

• Will not change when heated

• conduct electric current

What is the relationship between molecules and atoms?

• Molecules are combinations of two or more atoms.

• Molecules are the parts that make up atoms

• Molecules are the gaseous parts of atoms

• Molecules are atoms that have a positive charge

Tags

NGSS.MS-PS1-1

In the diagrams provided, the circles of different colors represent the atoms of different elements. Which diagram represents a mixture?

• I

• II

• III

• IV

Mixtures are different than pure substances because mixtures-

• have lower boiling points

• can be separated physically

• are less dense than pure substances

• contain only one type of atom

Which answer correctly matches diagram R?

• Elements

• Elemental Molecule

• Compound Molecule

• Mixture

Tags

NGSS.MS-PS1-1

Which of the following is true of oxygen?

• Oxygen is an element because its most basic unit is a single type of atom

• Oxygen is a compound because its most basic unit is a single type of atom.

• Oxygen is a mixture because its most basic unit contains more than one particle.

• Oxygen is a compound because its most basic unit contains more than one type of particle.

Tags

NGSS.MS-PS1-1

Beatriz wants to make a mixture out of her bowl of blueberries. Which of the following would turn her bowl of blueberries into a mixture?

• adding more blueberries to the bowl

• adding raspberries to the bowl

• cutting up the blueberries

• mashing the blueberries

Humans absorb oxygen from the air they breathe in and exhale carbon dioxide gas, CO2. Carbon dioxide gas is

• an element made of carbon and oxygen atoms.

• a solution made of carbon and oxygen atoms.

• a compound of carbon and oxygen atoms.

• a mixture of carbon and oxygen atoms.

Tags

NGSS.MS-PS1-1

Which answer correctly matches diagram O?

• Elements

• Elemental Molecule

• Compound Molecule

• Mixture

Tags

NGSS.MS-PS1-1