4. What are the characteristics of
the particles of matter?

Not sure how in depth or what level of particles but I will go as deep as I know. The matter that makes up the world is comprised of 12 particles which are known as fermions. There are 12 fermions which are made up of 6 quarks (up, charm, top, Down, Strange, Bottom) 3 electrons (electron, muon, tau) and three neutrinos (e, muon, tau). Technically, only the up quark, down quark, electron, and electron neutrino are necessary to create all known matter since others would simply be very unstable and decay into those particles. The other type of particles are known as Bosons. These particles transmit forces and all sorts of different interactions. I have included a photo from online which describes the main characteristics of each elementary particle.

a corroding iron, if that's one of your choices