Element Review

If something contains only a single type of atom or a single combination of atoms, it is called:

• pure

• a molecule

• chemical formula

• a compound

Tags

NGSS.MS-PS1-1

This is the smallest basic unit of matter.

• atom

• compound

• element

• molecule

Tags

NGSS.MS-PS1-1

Curium was named after...

• Curious George

• Steph Curry

• Albert Einstein

• Pierre and Marie Curie

Check all the elements:

• oxygen (O)

• hydrogen (H)

• water (H2O)

• gold (Au)

Tags

NGSS.MS-PS1-1

O3 is an element that is composed of 3 __________

• hydrogen atoms

• carbon atoms

• oxygen atoms

• water atoms

Tags

NGSS.MS-PS1-1

Which substance is NOT pure? (Just check one)

• oxygen

• hydrogen

• water

• mineral water

Answer explanation

Something is pure if it contains only a single type of atom or a single combination of atoms, such as a water molecule.

A substance that contains the same type of atom.

• atom

• compound

• element

• molecule

How many elements are found in nature?

• Around 25

• Around 90

• 118

• More than 200

What is true of elements? (Check all that apply)

• All of them are pure.

• They have to be bonded.

• A single atom can be an element.

Fill in the blank: The periodic table is a work in progress. That means that it's not ______________ yet.

Answer explanation

Scientists are still adding more elements to it.