Here's why:

* Continuous Spectrum: A continuous spectrum displays all colors of the rainbow, with no gaps or dark lines. This occurs when the atoms or molecules in a substance are very close together and interact strongly.

How each state produces a continuous spectrum:

* Solid: In a solid, atoms are tightly packed and interact frequently, leading to a wide range of energy levels. This allows for the emission of light across a wide range of wavelengths, creating a continuous spectrum.

* Liquid: Similar to solids, liquids also have atoms closely packed and interacting, although with slightly more freedom of movement. This still results in a continuous spectrum.

* Gas: While gases have atoms spread far apart, they can still produce a continuous spectrum when heated to high temperatures. At high temperatures, collisions between gas particles become more frequent and energetic, resulting in a wide range of energy levels and a continuous spectrum.

Note: While all three states can produce continuous spectra, they can also produce line spectra under specific conditions. For example, a gas at low pressure and excited by energy will emit a line spectrum.

Let me know if you want to learn more about line spectra!