3.21. Replacement Reactions http://www.ck12.org
Summary
- A replacement reaction occurs when elements switch places in compounds. This type of reaction involves
ions. Generally, more reactive elements replace less reactive elements. - A single replacement reaction occurs when one element replaces another element in one compound. This type
of reaction is represented by: A + BC→B + AC. - A double replacement reaction occurs when two ionic compounds exchange ions, producing two new ionic
compounds. This type of reaction is represented by: AB + CD→AD + CB.
Vocabulary
- replacement reaction: Chemical reaction in which ions switch places in one compound (single replacement)
or in two compounds (double replacement).
Explore More
Examine the double replacement reactions at the following URL. Watch the movies of the reactions, and relate the
molecular diagrams to the slides and still photos. Select one of the reactions, and write a paragraph describing
what occurs during the reaction. Explain how you can tell that a chemical change has occurred, and identify which
compound is the precipitate.
http://www.jce.divched.org/JCESoft/CCA/CCA1/R1MAIN/CD1R2360.HTM
Review
- What is a replacement reaction?
- Compare and contrast single and double replacement reactions, and give the general equation for each type of
reaction. - Which of the following reactions is not a replacement reaction?
a. Fe + CuSO 4 →FeSO 4 + Cu
b. 2Na + 2H 2 O→2NaOH + H 2
c. Zn + 2HCl→ZnCl 2 + H 2
d. 2Na + Cl 2 →2NaCl