Types of Chemical Reaction
A single-displacement reaction, also named single-replacement reaction, is a type of oxidation-reduction chemical reaction when an element or ion moves out of one compound and into another – that is, one element is replaced by another in a compound. This is represented by the general reaction scheme:
- A + B-C → A-C + B
- A and B may have different charge as ions and therefore some balancing of the equation may be necessary. For example, the reaction between silver nitrate, AgNO3 (which contains an Ag+ ion), and zinc, Zn, forms silver, Ag, and zinc nitrate, Zn(NO3)2 (which contains a Zn2+ion).
- 2AgNO3(aq) + Zn(s) → 2Ag(s) + Zn(NO3)2(aq)
All simple metal with acid reactions are single displacement reactions. For example, the reaction between magnesium, Mg, and hydrochloric acid, HCl, forms magnesium chloride, MgCl2, and hydrogen, H2.
- Mg(s) + 2 HCl(aq) → MgCl2(aq) + H2(g)