No exactly the contrary, white light is made up of light of all the colours of the rainbow. And you need to take that literally. The rainbow has these colours because rain acts as a prism and breaks...
It may, it may not. A neon lamp is close to monochromatic, but its ionised gas emits non-polarised light. A laser is the same - it's monochromatic *and* coherent, but the excited photons it emits are...
No, an incandescent bulb i.e. a bulb that emits light by the generation of heat, emits white light and is therefore not monochromatic. For a source to be monochromatic, the light emitted must be of a...