Balancing Review

What law governs the balancing of chemical equations? 

• Law of Energy
• Law of Conservation of Matter/Mass
• Law of Gravity
• Law of Matter Movement 

Tags

NGSS.MS-PS1-5

What is a coefficient?

• The small number on the right of the chemical symbol.
• The large number in front of a chemical formula.
• The number in between the chemical symbols.
• The number behind a chemical formula.

What is the part of the chemical equation in green called? 
Fe + S --> FeS

• products
• reactants
• yield
• chemical formula

What is the little number after an element in a chemical equation called.
Example: H₂

• Coefficient 
• Subscript
• Atom
• Equation

What is the right part of a chemical equation called...
2H_{2 +} O₂ --> 2H₂O

• Reactants
• Products 
• Yields 
• Chemical Equation 

Tags

NGSS.MS-PS1-5

What is the total number of atoms present in 5Na₃PO₄

• 5
• 40
• 55
• 8

Tags

NGSS.MS-PS1-1

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

• yes

• no

Tags

NGSS.MS-PS1-5

Balance this equation-

P₄ + O₂ --> P₂O₃

• P₄ + O₂ --> P₂O₃ (already balanced)

• P₄ + 3O₂ --> 2P₂O₃

• P₄ + O₂ --> 2P₂O₃

• 2P₄ + 3O₂ --> 2P₂O₃

Tags

NGSS.MS-PS1-5

Balance this equation.

Mg(NO₂)₂ + Na₂CO₃ --> NaNO₂ + MgCO₃

• Mg(NO₂)₂ + Na₂CO₃ --> NaNO₂ + MgCO₃ (already balanced)

• Mg(NO₂)₂ + Na₂CO₃ --> 2NaNO₂ + MgCO₃

• MgNO₂ + NaCO₃ --> NaNO₂ + MgCO₃

• Mg(NO₂)₂ + 2Na₂CO₃ --> 2NaNO₂ + 2MgCO₃

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Balance this equation,      
Al₂O₃ ---> Al + O₂ 

• Cannot be balanced
• 2Al₂O₃ ---> 2Al + 3O₂ 
• 2Al₂O₃ ---> 4Al + 3O₂ 
• 3Al₂O₃ ---> 2Al + O₂