You classify the equation as single replacement or double replacement. Single replacement has the form: A + BC --> AC + B. Double replacement has the form: AB + CD --> AD + BC.
1. a. Single replacement b. Al + Fe₂O₃ --> Al₂O₃ + Fe c. 2Al + Fe₂O₃ --> Al₂O₃ + 2Fe
2. a. Double replacement b. Pb(C₂H₃O₂)₂ + H₂S --> PbS + HC₂H₃O₂ c. Pb(C₂H₃O₂)₂ + H₂S --> PbS + 2 HC₂H₃O₂
3. a. Single Replacement b. Mg + HCl --> MgCl₂ + H₂ c. Mg + 2HCl --> MgCl₂ + H₂
4. a. Single Replacement b. Zn + Pb(NO₃)₂ --> Zn(NO₃)₂ + Pb c. Zn + Pb(NO₃)₂ --> Zn(NO₃)₂ + Pb
5. a. Double replacement b. AgNO₃ + NaCl --> AgCl + NaNO₃ c. AgNO₃ + NaCl --> AgCl + NaNO₃
6. a. Single replacement b. K + Ba(C₂H₃O₂)₂ --> KC₂H₃O₂ + Ba c. 2 K + Ba(C₂H₃O₂)₂ --> 2 KC₂H₃O₂ + Ba
7. a. Double replacement b. LiOH + Fe(NO₃)₃ --> Fe(OH)₃ + LiNO₃ c. 3 LiOH + Fe(NO₃)₃ --> Fe(OH)₃ + 3 LiNO₃
8. a. Single replacement b. CuO + H₂ --> Cu + H₂O c. CuO + H₂ --> Cu + H₂O
9. a. Single Replacement b. K + H₂O --> KOH + H₂ c. 2 K + 2 H₂O --> 2 KOH + H₂
