Balancing Chemical Equations

Balance the synthesis reaction 
__ C  + __ H₂  -->  __ CH₄

• 1,2,1
• 2,1,2
• 2,4,2
• 4,2,4

What are the product for the double replacement reaction?
CaCl₂   +  2AgNO₃  -->  2AgCl   +  Ca(NO₃)₂

• CaCl₂,  AgNO₃
• AgCl, Ca(NO₃)₂
• CaCl₂, Ca(NO₃)₂
• AgCl, AgNO₃

Balance the following single replacement reaction
Al  +  H₂O  -->  Al₂O₃  +  H₂

• 2Al  +  3H₂O  -->  Al₂O₃  +  6H₂
• 4Al  +  6H₂O  -->  2Al₂O₃  +  6H₂
• 2Al  + 3 H₂O  -->  Al₂O₃  +  3 H₂
• 2Al  +  H₂O  -->  Al₂O₃  +  H₂

What are the reactant(s) for the following decomposition reaction?
H₂O₂   -->  H₂O  +  O₂

• H₂O  +  O₂
• H₂O
• O₂
• H₂O₂

Balance the following synthesis reaction
 _P₄+_O₂ →  _P₂O₃

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

Balance the following double replacement reaction
_BaS + _PtF₂ → _BaF₂ + _PtS

• BaS + PtF₂ →   BaF₂ + PtS
• 4 BaS + 2 PtF₂ → BaF₂ +  PtS
• BaS + 2 PtF₂→            2 BaF₂ +  2 PtS
• BaS + 3 PtF₂ → BaF₂ +  2 PtS

Balance the following double replacement reaction. 
_HCN + _ CuSO₄ → _H₂SO₄ + _Cu(CN)₂

• 2HCN + CuSO₄ → H₂SO₄ +Cu(CN)₂
• HCN + 7CuSO₄  →  3H₂SO₄ + 8 Cu(CN)₂
• HCN + 2 CuSO₄ → H₂SO₄ + 2 Cu(CN)₂
• HCN + CuSO₄ → 2 H₂SO₄ + Cu(CN)₂

Balance the following combustion reaction
_C₃H₈  +  _O₂  -->  _CO₂  +  _H₂O

• C₃H₈  +  7O₂  -->  3CO₂  +  8H₂O
• C₃H₈  +  5O₂  -->  3CO₂  +  4H₂O
• 2C₃H₈  +  10O₂  -->  6CO₂  +  8H₂O
• C₃H₈  +  2O₂  -->  CO₂  +  2H₂O