Chemical properties are all those properties that are shown when the chemical is a part of a reaction or is changed in any way. Unlike physical properties, they affect the composition of the chemical and the way it behaves, while physical does not change the chemical itself. Such properties are toxicity, flammability, reaction with other elements, stability, and many more.
So combining blue with yellow light is like combining blue light with red and green light. The result of combining these three primary colors of light is to produce white light.
