Answer is: Velocity and spacing of particles is reduced and Volume of substance decreases relative to temperature decrease.
Charles' Law (The Temperature-Volume Law) - the volume of a given amount of gas held at constant pressure is directly proportional to the Kelvin temperature:
V₁/T₁ = V₂/T₂.
When temperature goes down, the volume also goes down.
Velocity is equivalent to a specification of its speed and direction of motion, it is a physical vector quantity. Less enegry (lower temperature), lower the velocity.
