In which substance do the particle move the fastest

GAS

Explanation:

The movement of the particles is fast in increasing order of Solid< Liquid< Gas. The particles move faster in fluids which are liquids and gases. The movement of the particles of a substance depends on many factors like temperature, pressure, viscosity of the fluid, density, surface or environment in/on which its flowing.

The rise in temperature of the substance increases the kinetic energy of its particles which makes them to move faster. The increase in temperature of the solids up to a certain point melts them which allows them to flow, causing the particles to move faster than before, also on increasing the temperature of the liquids converts them to gas which makes their particles to move more rapidly and freely.