In-Depth Notes on Single Replacement Reactions

Unit: Chemical Reactions

Types of Chemical Reactions: Single Replacement

Learning Objectives

• Identify a single replacement reaction.
• Predict the products of single replacement reactions in words.

Definition of Single Replacement Reactions

• Single replacement reactions occur when an element reacts with a compound, producing a new element and a new compound.
• Common Form:
  $\text{Element} + \text{Compound} \rightarrow \text{Element} + \text{Compound}$
  Example:
  $A + BC \rightarrow AC + B$

Conditions for Reactions

• Not all proposed single replacement reactions will occur.
• Use the activity series to determine if the reaction will take place.
• Rule: "Like replaces like" (e.g., metals replace metals, nonmetals replace nonmetals).

Activity Series of Metals

• The activity series lists metals (and hydrogen) in order of decreasing reactivity.
  • Examples include:
  1. Lithium (Li)
  2. Potassium (K)
  3. Barium (Ba)
  4. Strontium (Sr)
  5. Calcium (Ca)
  6. Sodium (Na)
  7. Cesium (Cs)
  8. Beryllium (Be)
  9. Magnesium (Mg)
  10. Aluminum (Al)
  11. Zinc (Zn)
  12. Chromium (Cr)
  13. Gallium (Ga)
  14. Iron (Fe)
  15. Cobalt (Co)
  16. Nickel (Ni)
  17. Tin (Sn)
  18. Lead (Pb)
  19. Hydrogen (H)
  20. Copper (Cu)
  21. Mercury (Hg)
  22. Silver (Ag)

Examples of Single Replacement Reactions

1. Metal Replacement

   • Reaction: $\text{Li} + \text{Zn(C}<em>2\text{H}</em>3\text{O}<em>2) \rightarrow \text{Zn} + \text{Li(C}</em>2\text{H}<em>3\text{O}</em>2)$
   • Explanation: Lithium is more reactive than zinc, so it replaces zinc in the compound.

2. No Reaction

   • Reaction: $\text{Cu} + \text{Al}<em>2\text{(SO}</em>4)_3 \rightarrow \text{No Reaction}$
   • Explanation: Copper cannot replace aluminum, as it is less reactive.

3. Hydrogen Replacement by Metal

   • Reaction: $\text{Na} + \text{H}<em>2\text{O} \rightarrow \text{NaOH} + \text{H}</em>2$
   • Helpful Tip: Convert water into "hydrogen hydroxide" before predicting products.

4. Hydrogen Replacement in Acids

   • Reaction: $\text{Ca} + \text{H}<em>3\text{PO}</em>4 \rightarrow \text{Ca(H}<em>2\text{PO}</em>4) + \text{H}_2$
   • Helpful Tip: Convert acid names into their ionic forms.

5. Non-Metal Replacement

   • Reaction: $\text{F}<em>2 + \text{MgI}</em>2 \rightarrow \text{Mg} + \text{I}<em>2\text{F}</em>2$
   • Tip: Ensure non-metals are replaced by non-metals.

Activity Series of Non-Metals

• Listed in order of decreasing activity:
  • Fluorine (F)
  • Chlorine (Cl)
  • Bromine (Br)
  • Iodine (I)