Learn about types of chemical reactions, including combination, decomposition, and displacement reactions.
A combination reaction joins two or more substances into one product. A decomposition reaction breaks one substance into two or more products.
Hydrogen and oxygen combine to form water. What type of reaction is this?
Combination reaction
Heating calcium carbonate produces calcium oxide and carbon dioxide. What type of reaction is this?
Decomposition reaction
Sodium and chlorine combine to form sodium chloride. What type of reaction is this?
Combination reaction
In a displacement reaction, a more reactive element displaces a less reactive element from its compound.
Iron placed in copper sulfate solution displaces copper. What type of reaction is this?
Displacement reaction, since iron is more reactive than copper
Why must the displacing element be more reactive than the one it replaces?
Because a less reactive element cannot force out a more reactive one from its compound
Magnesium displaces hydrogen from hydrochloric acid to form magnesium chloride and hydrogen gas. What type of reaction is this, and what does it tell us about reactivity?
Displacement reaction; it tells us magnesium is more reactive than hydrogen
1. What is a combination reaction?
2. What is a decomposition reaction?
3. What is a displacement reaction?
4. Zinc displaces copper from copper sulfate solution. What does this tell us about their reactivity?
5. Give an example of a decomposition reaction.
6. Hydrogen and chlorine combine to form hydrogen chloride. What type of reaction is this?
7. Heating potassium chlorate produces potassium chloride and oxygen. What type of reaction is this?
8. Copper displaces silver from silver nitrate solution. What does this tell us about their reactivity?
9. Why can't a less reactive element displace a more reactive one from its compound?
10. Give an example of a combination reaction from daily life.