"electromagnetic radiation travels or propagates through space in the form of a wave but can interact with matter as a particle of energy called a photon. this dual nature is referred to as":

"Electromagnetic radiation travels or propagates through space in the form of a wave but can interact with matter as a particle of energy called a photon. This dual nature is referred to as" Wave particle duality  (answer)

Explanation:

Electromagnetic radiation is created when an atomic particle, such as an electron, is accelerated by an electric field, causing it to move, and it is a form of energy that spreads as both magnetic and electrical waves that travels in vessels of energy called photons.

All types of electromagnetic radiation travel at the speed of light, radiation can be also described in terms of particles of energy, called photons. Electromagnetic radiation is generated when an electrical charge is accelerated. The acceleration produces oscillating electric and magnetic fields. Electromagnetic radiation ranges from gamma rays with very short wavelength to long radio waves. Electromagnetic radiation has the dual nature: its exhibits wave properties and photon properties.

Waves are characterized by frequency, wavelength, speed and phase, where as, a photon is the basic unit of all light. Wave particle duality can be explained as when an entity exhibits a wavelike and a particlelike properties though these properties never appear simultaneously.

heat the gas and measure the pressure