--- ## Definition - An electron is a negatively charged particle that surrounds the nuclei of an atom. Electrons are what give many elements their chemical properties such as reactivity and so on. --- ## Characteristics - The weight of an electron is 9.11 x 10^-31 - Electrons force an **atom** to emit [[Light]] or [[Photon]] when they move from a higher Energy level to a lower one. *See [[Orbitals]] for more* - Electrons are what allow atoms to form bonds with other atoms, thus creating Molecules or Compounds. This is because electrons can be shared or given to other atoms. >[!tip] >##### Charge to mass ratio of an electron: $-1.76*10^8$ > > --- ## Quantum mechanical properties - According to [[Quantum mechanics]] electrons like [[Photon]]s are both a particle and a wave *(which is something known as wave-particle duality)*. - Quantum mechanics describes electrons in [[Orbitals]] as a standing wave with **nodes** or points along that wave that don't move. This is because it is impossible to know their exact location or velocity *(see [[Quantum mechanics]] for more information on this)*. --- ## Effective nuclear charge - The effective nuclear charge of an atom is **the attractive positive charge of nuclear protons acting on valence electrons**. Electrons shielding an atom's nucleus will push against other electrons preventing any one electron from experiencing the nuclei's *maximum nuclear charge*. - Effective nuclear charge **increases towards the top left of the periodic table** since those atoms have the smallest size and a few other factors. - See [[Orbitals]] for more. --- #subpage