Grade 8 Chemical Reactions & Equations Review

Which side of a chemical equation is the reactant side?

• Left (before the arrow)

• Right (after the arrow)

Which side of a chemical equation os the product side?

• Left (before the arrow)

• Right (after the arrow)

Which problem is balanced?

• PbO₂ + 2H₂
• SO₂ + H₂0 --> H₂SO₄
• 2Na + 2H₂O --> 2NaOH + H₂

Is the equation balanced?: 2H₂O + O₂ --> 4MgO + 3Fe

• Yes
• No

Tags

NGSS.MS-PS1-5

Balance this equation:
MgCl₂ --> Mg₄+ Cl₂

• It's already balanced.
• 4MgCl₂ --> Mg₄+ 4Cl₂
• 4MgCl₂ --> Mg₄+ 5Cl₂

Tags

NGSS.MS-PS1-5

Balance this equation:
 2Li + Cl₂ -> LiCl

• 2Li + Cl₂ -> 4LiCl2
• 2Li + Cl₂ -> LiCl₂
• 2Li + Cl₂ -> 2LiCl

At the end of chemical reactions, what is the total mass of the reactants compared to the total mass of the products?

• the product is doubled
• the product is half the mass of the reactants
• the mass is the same
• the mass changes depending on the reaction

How many atoms of aluminum are on each side of the following equation: 4Al + 3O₂ --> 2Al₂ O₃

• 2
• 6
• 1
• 4

Balance this equation 
Ca + H₂O --> CaO + H₂

• Ca + 2H₂O --> CaO + 2H₂
• 2Ca + H₂O --> CaO + H₂
• It is already balanced
• Cannot be balanced

Is the following equation balanced or unbalanced?
Fe + S --> FeS

• balanced
• unbalanced