Electron

Definition

An electron is a subatomic particle with a negative charge that orbits the nucleus of an atom. It plays a vital role in chemical bonding, electrical conductivity, and the formation of ions and molecules. The arrangement and behavior of electrons determine the chemical properties of an element, influencing how it interacts with other atoms and participates in reactions.

5 Must Know Facts For Your Next Test

1. Electrons have a very small mass, approximately 1/1836 that of a proton, which allows them to move freely around the nucleus.
2. The arrangement of electrons in an atom is organized into energy levels or shells, with each shell holding a specific maximum number of electrons.
3. Electrons are responsible for forming bonds between atoms; when they are shared or transferred, they create covalent or ionic bonds, respectively.
4. In its neutral state, an atom has an equal number of protons and electrons, balancing out their opposite charges.
5. Electrons can absorb energy and move to higher energy levels or release energy and fall back to lower levels, which is essential for phenomena such as light emission in atoms.

Review Questions

• How do electrons influence the chemical properties of an atom?
  • Electrons influence the chemical properties of an atom primarily through their arrangement and interactions. The number of valence electrons determines how an atom bonds with others, which dictates its reactivity and ability to form compounds. Atoms with similar electron configurations exhibit similar chemical behaviors, meaning that understanding electron placement is key to predicting how elements will react.
• Explain the difference between ionic and covalent bonds in terms of electron behavior.
  • Ionic bonds occur when one atom transfers electrons to another atom, leading to the formation of positively and negatively charged ions. In contrast, covalent bonds involve the sharing of electrons between two atoms. The way electrons behave—whether they are lost, gained, or shared—defines the type of bond formed and ultimately influences the structure and properties of molecules.
• Evaluate how changes in electron energy levels can affect an atom's interaction with electromagnetic radiation.
  • When electrons absorb energy from electromagnetic radiation, they can move to higher energy levels or excited states. This process is crucial in phenomena such as spectroscopy, where different elements emit specific wavelengths of light based on the transitions of electrons between these energy levels. Understanding these interactions allows us to analyze elemental composition and behavior in various applications, from astronomy to material science.

Related terms

Proton:

A positively charged subatomic particle found in the nucleus of an atom, which, along with neutrons, makes up the atom's mass.

Neutron: A neutral subatomic particle located in the nucleus of an atom, contributing to the atomic mass but not affecting its charge.

Ion:

An atom or molecule that has gained or lost one or more electrons, resulting in a net electric charge.