balancing reactions

_P₄+_O₂ →  _P₂O₃

• 3 P₄+1 O₂ → 2 P₂O₃
• 1 P₄+1 O₂ → 2 P₂O₃
• 1 P₄+ 3 O₂ → 2 P₂O₃
• 1 P₄+ 2 O₂ → 3 P₂O₃

Tags

NGSS.HS-PS1-7

_Al + _HCl →_H₂ + _AlCl₃

• 2 Al + 2 HCl → 2 H₂ + 6 AlCl₃
• 3 Al + 3 HCl → 6 H₂ + 2 AlCl₃
• 1 Al + 1 HCl → 3 H₂ + 1 AlCl₃
• 2 Al + 6 HCl → 3 H₂ + 2 AlCl₃

Tags

NGSS.HS-PS1-7

_K + _Cl₂ →_KCl

• 2 K + 16 Cl₂ → 8 KCl
• 2 K + 1 Cl₂ → 2 KCl
• 3 K + 4 Cl₂ → 3 KCl
• 1 K + 1 Cl₂ →1 KCl

Tags

NGSS.HS-PS1-7

_NaF + _Br₂ →_NaBr + _F₂

• 1NaF + 2 Br₂ →1 NaBr + 2 F₂
• 2NaF + 2 Br₂ → 2 NaBr + 2 F₂
• 2 NaF + 3 Br₂ → 1 NaBr + 2 F₂
• 2 NaF + 1 Br₂ → 2 NaBr + 1 F₂

Tags

NGSS.HS-PS1-7

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

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

Tags

NGSS.HS-PS1-7

How many total atoms are represented?         4Al₂O₃

• 2
• 8
• 5
• 20

Tags

NGSS.MS-PS1-1

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

• balanced
• unbalanced

Tags

NGSS.HS-PS1-7

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

• products
• reactants
• yield
• chemical formula

__Na + __Cl₂ --> __NaCl

• 1,1,2
• 2,1,2
• 2,1,1
• already balanced

Tags

NGSS.HS-PS1-7

What does the Law of Conservation of Mass state?

• Matter cannot be gained or lost in a chemical reaction.
• Matter can only be lost in a chemical reaction.
• Matter can only be gained in a chemical reaction.
• Matter can be gained and lost in a chemical reaction. 

Tags

NGSS.HS-PS1-7