Chemical Reactions

Which of the following is a balanced chemical equation?​

• H₂ + O₂ → H₂O​

• 2H₂ + O₂ → 2H₂O​

• H₂ + 2O₂ → H₂O₂​

• 2H₂ + 2O₂ → 2H₂O​

What is the coefficient of O₂ when the equation C₃H₈ + O₂ → CO₂ + H₂O is balanced?​

• 3​

• 4​

• 5​

• 6​

Which of the following observations indicates a chemical reaction has occurred?​

• Change in color​

• Formation of a precipitate​

• Emission of gas​

• All of the above​

In the reaction Zn + CuSO₄ → ZnSO₄ + Cu, which species is oxidized?​

• Zn​

• Cu​

• SO₄²⁻​

• ZnSO₄​

What type of reaction is represented by the equation HCl + NaOH → NaCl + H₂O?​

• Synthesis​

• Decomposition​

• Single displacement​

• Neutralization​

Balance the equation: Al + O₂ → Al₂O₃. What is the coefficient of Al?​

• 1​

• 2​

• 3​

• 4​

Which of the following is a decomposition reaction?​

• 2H₂O → 2H₂ + O₂​

• H₂ + Cl₂ → 2HCl​

• NaOH + HCl → NaCl + H₂O​

• Zn + 2HCl → ZnCl₂ + H₂​

In the reaction 2KClO₃ → 2KCl + 3O₂, what is the mole ratio of KClO₃ to O₂?​

• 1:1​

• 2:3​

• 3:2​

• 1:2​

Which of the following is a single displacement reaction?​

• 2Na + Cl₂ → 2NaCl​

• Mg + 2HCl → MgCl₂ + H₂​

• CaCO₃ → CaO + CO₂​

• C + O₂ → CO₂​

Identify the spectator ion(s) in the reaction: AgNO₃ + NaCl → AgCl + NaNO₃.​

• Ag⁺ and Cl⁻

• Na⁺ and NO₃⁻

• Ag⁺ and NO₃⁻

• Na⁺ and Cl⁻