Is an x ray physical or chemical?
X Rays are electromagnetic radiation, like visible light but of much shorter wavelength (so not visible to the eye). Like all electromagnetic radiation, they have some aspects of their nature that are more like waves, and other aspects that are more like particles. But essentially, they result from the oscillation of electric and magnetic fields. So you would not really classify them as "matter". They would therefore not be classed as physical "things", and are definitely not chemicals.
So the answer is they are neither, they are electromagnetic radiation (of a specific wavelength).