Classify chemical reactions as synthesis, decomposition, single replacement, or double replacement.

Let’s go through each reaction one by one and classify it based on the type of chemical reaction.

We’ll use these simple definitions:

- Synthesis: Two or more things combine to make ONE new thing. (A + B → AB)
- Decomposition: ONE thing breaks apart into two or more simpler things. (AB → A + B)
- Single Replacement: One element kicks out another in a compound. (A + BC → AC + B)
- Double Replacement: Two compounds swap partners. (AB + CD → AD + CB)

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1. KClO₃ → KCl + O₂
One compound breaks into two products → decomposition

2. HCl + NaOH → NaCl + H₂O
Acid + base → salt + water — this is double replacement (ions swap) → double replacement

3. Mg + 2HCl → MgCl₂ + H₂
Magnesium replaces hydrogen in HCl → single replacement

4. H₂ + O₂ → H₂O
Two elements combine to form one compound → synthesis

5. Al + NiBr₂ → AlBr₃ + 3Ni
Aluminum replaces nickel → single replacement

6. Al + 3O₂ → Al₂O₃
Two elements combine → synthesis

7. NaCl → Na + Cl₂
One compound breaks into elements → decomposition

8. CaCl₂ + F₂ → CaF₂ + Cl₂
Fluorine replaces chlorine → single replacement

9. AgNO₃ + KCl → AgCl + KNO₃
Ions swap between two compounds → double replacement

10. N₂ + H₂ → NH₃
Two elements combine → synthesis

11. H₂O₂ → H₂O + O₂
One compound breaks down → decomposition

12. (NH₄)₂SO₄ + Ba(NO₃)₂ → BaSO₄ + NH₄NO₃
Two compounds swap ions → double replacement

13. MgI₂ + Br₂ → MgBr₂ + I₂
Bromine replaces iodine → single replacement

14. SO₃ + H₂O → H₂SO₄
Two compounds combine to make one → synthesis

15. KCl + Zn₃(PO₄)₂ → ZnCl₂ + K₃PO₄
Wait — let’s check if this is balanced? Actually, for classification, we don’t need to balance — just see the pattern.
It looks like potassium and zinc are swapping places → double replacement

*(Note: The equation as written isn’t balanced — but since the question only asks to classify, we go by the pattern shown.)*

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Final Answer:

1. decomposition
2. double replacement
3. single replacement
4. synthesis
5. single replacement
6. synthesis
7. decomposition
8. single replacement
9. double replacement
10. synthesis
11. decomposition
12. double replacement
13. single replacement
14. synthesis
15. double replacement