Fehling’s reagent is actually a mixture of two solutions: Fehling’s A and Fehling’s B. Fehling’s A is a clear blue solution, while Fehling’s B is a clear colorless solution. When these two solutions are mixed together, they form an opaque brick-red precipitate, which is the characteristic color associated with Fehling’s reagent. This reaction is commonly used to test for the presence of reducing sugars, such as glucose, in a solution.