what are three ways to recognize if a single displacement reaction has taken place?

Question

 Single Displacement question

Answer 1

1. Color change

2. Formation of bubbles (a gas)

3. Formation of a precipitate

 

A single replacement/displacement is a reaction where 1 element replaces another in a compound.  A metal will only displace a metal and a non metal will displace a non metal, and only a more active metal can replace a less active one.