Electrons

Negative electrons attract positive electrons.

An atom is made out of protons, neutrons and electrons.

Positive atomic nuclei attract negative electrons.

Good conductors of heat are usually good conductors of electricity, but that puts the causal relation backwards. Conduction-band electrons can't help but transport kinetic energy, which--randomized--is heat. Putting heat before electricity is reasonable only because of the rarity of materials like diamond that conduct heat via the quasi-particles called phonons, which are communicable crystal-lattice vibrations.

Atoms are composed of protons, neutrons, and electrons.

Electrons orbit around the nucleus of the atom.

Each kind of atom has a certain unique number of particles called protons, neutrons, and electrons in it.

The protons and neutrons cluster together in the center of the atom in what is called the nucleus. The electrons orbit around the nucleus.

Helium is the second simplest atom. It consists of a nucleus containing 2 protons and 2 neutrons. Around the nucleus orbits 2 electrons.

Protons have a positive charge, electrons have a negative charge, and neutrons have no charge.