You find a yellow rock and wonder if it is gold. how could you apply the scientific method to this problem

You need to form a hypothesis based on what is already known about gold and then devise an experiment to test this hypothesis.

For example, the density of gold is well known. So your hypothesis would be that if the rock were gold, you could predict the amount of water displacement in a beaker simply by measuring the weight of the rock.

The steps would be:

1. research what is already known about your field of investigation (in this case gold).

2. Using that information, formulate a hypothesis that allows you to make predictions.

3. Devise an experiment that can test your predictions.