The element oxygen, represented by the symbol O, is classified as

• Element

• a compound

• a mixture

• a solution

What is a compound?

• Two or more different elements bonded together.

• Two of the same elements bonded together.

• A mixture of different substances.

• Two substances stuck together with glue.

Why is it impossible to see molecules with the naked eye?

• they are too big
• they are too small
• they are too fast
• they have no mass

Which of these compounds has the most atoms?

• CO2
• C6,H12,O6
• O2
• Na,Cl,He,O3

Tags

NGSS.MS-PS1-1

At room temperature, oxygen is a gas and hydrogen is a gas. When they combine, they form a H20 , this is a 

• solid

• liquid

• gas

• solution

A water molecule contains

• one hydrogen atom and two oxygen atoms
• two hydrogen atoms and one oxygen atom
• two hydrogen atoms and two oxygen atoms
• two hydrogen atoms and no oxygen atoms

Tags

NGSS.MS-PS1-1

Elements are made of 

• many types of atoms 
• the periodic table
• one type of atom 
• molecules 

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NGSS.MS-PS1-1

What are the 3 particles that make-up the atom?

• protons, neutrons, and isotopes
• neutrons, isotopes, and electrons
• positives, negatives, and electrons
• protons, neutrons, and electrons

Tags

NGSS.MS-PS1-1

What is the basic smallest piece of matter?

• Atoms

• Elements

• Compounds

• Molecules

How many hydrogen atoms are there in a water molecule? 

• 0
• 1
• 2
• 3

Tags

NGSS.MS-PS1-1