<span>After many experiments and many different approaches to the question, the scientist may be able to develop a theory. The theory explains why nature behaves in the way described by the natural law. It answers not only the original question, but also any other questions that were raised during the process. The theory also predicts the results of further experiments, which is how it is checked. Theories are not the end of the process.</span>
Explanation:
When a metal replaces another metal in solution, we say such a reaction has undergone a single displacement reaction.
In such a reaction, metal higher up in the activity series replaces another one due to their position.
To known the metal or metals that will replace the given copper, we need to reference the activity series of metals.
Every metal higher than copper in the series will displace copper from the solution.
So, there metals are: potassium, sodium, lithium, barium, strontium etc.