Final answer:
Motion lines and spacing in a drawing of metal atoms symbolize the kinetic energy and atomic spacing, which increase with temperature. at room temperature the metal's structure can withstand shaking without losing electrons, whereas heating increases atomic motion enough to 'boil off' electrons.
Step-by-step explanation:
The question regarding motion lines and spacing in relation to the difference in the atoms of a metal at room temperature compared to when the metal is heated falls under the field of Physics. In a metal at room temperature, the atoms are in a regular lattice structure with free electrons that move throughout this lattice. When the metal is shaken, the amount of energy involved merely translates to vibrations within this structure; thereby, no electrons 'fall out' due to insufficient energy to free them from the metallic bond.However, when the metal is heated, the addition of thermal energy increases the vibration of atoms, and this increased motion results in more energetic collisions.
These collisions can provide enough energy for electrons to escape the attraction of the nuclei, which is often referred to as the 'boiling off' of electrons. The motion lines drawn would be longer and spacing between them would increase with the increased atomic motion at higher temperatures, symbolizing the increased kinetic energy of both atoms and free electrons. This understanding comes from the principles that define the behaviour of particles at the atomic level in the context of temperature changes, energy distribution, and thermal excitation.