State three properties of cathode rays which suggest the particle nature of matter

Answer Details

Three properties of cathode rays which suggest the particle (corpuscular) nature of matter are:

1. They travel in straight lines and cast sharp shadows of objects placed in their path, as would a stream of moving particles.
2. They are deflected by electric and magnetic fields, showing that they consist of charged particles (electrons carrying negative charge) that possess mass and charge.
3. They possess momentum and kinetic energy - they can exert a mechanical force, for example turning a small paddle wheel placed in their path, which shows the moving stream carries the properties of particles.

(They also produce heat on striking a target and can be deflected/behave as though made of discrete massive particles.)