Use the periodic table to match each element with its symbol.

hydrogen ​ (a)   , helium ​ (b)   , iron ​ (c)   , oxygen ​ (d)   , potassium ​ (e)  

• H
• He
• Fe
• O
• k
• I
• P

Use the periodic table to complete the information about the atoms in the molecule shown.

Na: Name & How many?

O: Name & How many?

H: Name & How many?

Which chemical formula represents the molecule shown?

• SOH

• NaOH

• Na(OH)₂

• Na₂(OH)₂

Match the chemical formula to identify each model shown.

• CO₂

• 
• O₂

• 
• NH₃

• 
• H₂O

• 

Enter numbers in the blanks beside the photo to show the number of atoms of each element that make up a unit of the mineral.

hematite: Fe₂O₃

​ (a)   iron

​ (b)   oxygen

• 3
• 2
• 1
• 4
• 5
• 6
• 7
• 8
• 9
• 10

Enter numbers in the blanks beside the photo to show the number of atoms of each element that make up a unit of the mineral.

halite: NaCl

​ (a)   sodium. ​ (b)   chlorine

• 1
• 2
• 3
• 5
• 4
• 6
• 7
• 8
• 9
• 10

Enter numbers in the blanks beside the photo to show the number of atoms of each element that make up a unit of the mineral.

pyrite: FeS₂

​ (a)   iron, ​ (b)   sulfur

• 2
• 1
• 3
• 4
• 5
• 6
• 7
• 8
• 9
• 10

Enter numbers in the blanks beside the photo to show the number of atoms of each element that make up a unit of the mineral.

grossular: Ca₃Al₂(SiO₄)₃

​ (a)   calciyum, ​ (b)   aluminum, ​ (c)   silicon, ​ (d)   oxygen

• 3
• 2
• 12
• 1
• 4
• 5
• 6
• 7
• 8
• 9

Enter numbers in the blanks beside the photo to show the number of atoms of each element that make up a unit of the mineral.

malachite: Cu₂CO₃(OH)₂

​ (a)   copper, ​ (b)   carbon, ​ (c)   oxygen, ​ (d)   hydrogen

• 2
• 1
• 5
• 3
• 4
• 6
• 7
• 8
• 9
• 10

Compare the total number of atoms you began with compared to the total number of atoms you ended with after rearranging the models.

• The number of atoms decreased.

• The number of atoms stayed the same.

• The number of atoms increased.