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Identifying types of reactions

Synthesis, decomposition, single and double replacement, combustion.

The common mistake

Mixing up single replacement (element swaps into a compound) with double replacement (two compounds swap partners).

Instead: Count what's on the left: element + compound → single replacement; compound + compound → double replacement; fuel + O₂ → combustion.

Worked example with Guide me

Classify Zn + CuSO₄ → ZnSO₄ + Cu.

  1. Sugar · What's on the left?
    Student · An element and a compound.
  2. Sugar · What happens?
    Student · Zinc takes copper's place.

Answer: Single replacement

Try 3 practice questions

  1. 1. 2H₂O → 2H₂ + O₂ is…?

    Show answer

    Decomposition

  2. 2. AgNO₃ + NaCl → AgCl + NaNO₃ is…?

    Show answer

    Double replacement

  3. 3. CH₄ + 2O₂ → CO₂ + 2H₂O is…?

    Show answer

    Combustion

Quick answers

What is the most common mistake with identifying types of reactions?
Mixing up single replacement (element swaps into a compound) with double replacement (two compounds swap partners).
How do I get identifying types of reactions right?
Count what's on the left: element + compound → single replacement; compound + compound → double replacement; fuel + O₂ → combustion.
Can you show a worked example?
Classify Zn + CuSO₄ → ZnSO₄ + Cu. Single replacement

Related concepts

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