Electrons

Definition

Electrons are negatively charged subatomic particles that are found in the atoms of all elements. They are responsible for many of the chemical and physical properties of matter, including the formation of chemical bonds and the flow of electrical current.

5 Must Know Facts For Your Next Test

1. Electrons are found in the negatively charged cloud surrounding the positively charged nucleus of an atom.
2. The number of electrons in an atom determines its chemical identity and reactivity.
3. Electrons can be gained, lost, or shared in chemical reactions to form ionic or covalent bonds.
4. The arrangement of electrons in an atom's energy levels or shells is described by the Bohr model.
5. Valence electrons, the electrons in the outermost shell, are responsible for an atom's chemical properties and behavior.

Review Questions

• Explain the role of electrons in the context of atomic structure and symbolism.
  • Electrons are the key component of atomic structure, as they determine an element's chemical identity and properties. The number of electrons in an atom, particularly the valence electrons in the outermost shell, dictates how that element will interact and form bonds with other elements. Atomic symbols and formulas represent the specific arrangement of protons and electrons within an atom, allowing chemists to predict and understand the behavior of different substances.
• Describe how the Bohr model of the atom depicts the behavior of electrons.
  • The Bohr model represents the atom as a central nucleus surrounded by electrons orbiting in discrete energy levels or shells. This model suggests that electrons can only occupy certain allowed energy levels, and transitions between these levels are accompanied by the absorption or emission of specific quanta of energy. The Bohr model helps explain the stability of atoms, the emission of light by excited atoms, and the chemical reactivity of elements based on their electron configuration.
• Analyze the importance of electrons in the context of chemical bonding and reactivity.
  • Electrons are the driving force behind chemical reactivity and the formation of chemical bonds. Atoms will gain, lose, or share electrons to achieve a more stable electron configuration, often by filling their outermost valence shell. The ability of atoms to donate, accept, or share electrons determines the type of chemical bond formed, whether ionic, covalent, or metallic. Understanding the behavior of electrons is crucial for predicting the products of chemical reactions and explaining the properties of different substances at the atomic level.

Related terms

Atomic Structure: The arrangement of protons, neutrons, and electrons within an atom, which determines the element's chemical properties.

Bohr Model: A model of the atom that depicts electrons orbiting the nucleus in discrete energy levels or shells.

Valence Electrons: The electrons in the outermost shell of an atom that participate in chemical reactions and bonding.