covalent radius

Examples of covalent radius in the following topics:

• Bond Lengths

  • The covalent radius of an atom is determined by halving the bond distance between two identical atoms.
  • Based on data for the H2 molecule, the covalent radius of H is 37 pm.
  • Covalent radii can be used to estimate the bond distance between two different atoms; it is the sum of the individual covalent radii.
  • This trend is identical to that of the atomic radius.

• Properties of Hydrogen

  • However, monoatomic hydrogen is rare on Earth is rare due to its propensity to form covalent bonds with most elements.
  • Its covalent radius is 31.5 pm.
  • Many of the hydrogen atom's chemical properties arise from its small size, such as its propensity to form covalent bonds, flammability, and spontaneous reaction with oxidizing elements.

• Atomic Radius

  • The atomic radius is one such characteristic that trends across a period and down a group of the periodic table.
  • Depending on context, the term atomic radius may apply only to isolated atoms, or also to atoms in condensed matter, covalently bound in molecules, or in ionized and excited states.
  • The value of an atomic radius may be obtained through experimental measurements or computed with theoretical models.
  • Under some definitions, the value of a radius may depend on the atom's state and context.
  • A chart showing the atomic radius relative to the atomic number of the elements.

• Percent Ionic Character and Bond Angle

  • Chemical bonds are more varied than terminology might suggest; they exist on a spectrum between purely ionic and purely covalent bonds.
  • The average radius of the neutral Li atom is about 2.52Å.
  • The electron-pair bond is clearly responsible for this situation; this provides the covalent bond's stability.
  • The more covalent in nature the bond, the more likely the atoms will situate themselves along the predetermined vectors given by the orbitals that are involved in bonding (VSEPR theory).
  • Does this make an ionic bond, a covalent bond, or something in between?

• Carbides

  • Carbides are compounds composed of carbon and less electronegative elements and they are distinguished by their chemical bonding (ionic, covalent).
  • Covalent carbides are found in carbides of silicon and boron.
  • The reason these two elements form "covalent" carbides is due to their similar electronegativity and size to carbon.
  • Because of this, their association is completely covalent in character.
  • They are formed so that the carbon atoms fit into octahedral interstices in a close-packed metal lattice when the metal atom's radius is greater than ~135 pm.

• Ionic vs Covalent Bond Character

  • There are multiple kinds of attractive forces, including covalent, ionic, and metallic bonds.
  • Bonds that fall in between the two extremes, having both ionic and covalent character, are classified as polar covalent bonds.
  • Though ionic and covalent character represent points along a continuum, these designations are frequently useful in understanding and comparing the macroscopic properties of ionic and covalent compounds.
  • This bond is considered to have characteristics of both covalent and ionic bonds.
  • Discuss the idea that, in nature, bonds exhibit characteristics of both ionic and covalent bonds

• Properties of Carbon

  • As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds.
  • Carbon has an affinity for bonding with other small atoms, including other carbon atoms, via the formation of stable, covalent bonds.
  • The exotic 19C exhibits a nuclear halo, which means its radius is appreciably larger than would be expected if the nucleus were a sphere of constant density.

• Physical Properties of Covalent Molecules

  • The covalent bonding model helps predict many of the physical properties of compounds.
  • First described by Gilbert Lewis, a covalent bond occurs when electrons of different atoms are shared between the two atoms.
  • Several physical properties of molecules/compounds are related to the presence of covalent bonds:
  • Covalent compounds do not conduct electricity; this is because covalent compounds do not have charged particles capable of transporting electrons.
  • However, the Lewis theory of covalent bonding does not account for some observations of compounds in nature.

• Covalent Bonds

  • Covalently sharing two electrons is also known as a "single bond."
  • Covalently sharing two electrons is also known as a "single bond."
  • Covalent bonding interactions include sigma-bonding (σ) and pi-bonding (π).
  • In non-polar covalent bonds, the electrons are equally shared between the two atoms.
  • Covalent compounds, on the other hand, have lower melting and boiling points.

• Types of Bonds

  • Pure ionic bonding cannot exist: all ionic compounds have some degree of covalent bonding.
  • Bonds with partially ionic and partially covalent character are called polar covalent bonds.
  • A covalent bond involves electrons being shared between atoms.
  • This difference in charge is called a dipole, and when the covalent bond results in this difference in charge, the bond is called a polar covalent bond.
  • A rule of thumb is that covalent compounds are more difficult to change than ionic compounds.