0
Rate this Study Guide:
☆☆☆☆☆Ra and Ac
Pu and Th
Am and U
shell
it increases
ionic bond
radioactive
The molecular geometry of a molecule can be determined using the VSEPR theory.
VSEPR (Valence Shell Electron Pair Repulsion) Theory: The basic premise of this simple theory is that electron pairs (bonding and nonbonding) repel one another; so the electron pairs will adopt a geometry about an atom that minimizes these repulsions. Use the method below to determine the molecular geometry about an atom.
Write the Lewis dot structure for the molecule.
Count the number of things (atoms, groups of atoms, and lone pairs of electrons) that are directly attached to the central atom (the atom of interest) to determine the overall (electronic) geometry of the molecule.
Now ignore the lone pairs of electrons to get the molecular geometry of the molecule. The molecular geometry describes the arrangement of the atoms only and not the lone pairs of electrons. If there are no lone pairs in the molecule, then the overall geometry and the molecular geometry are the same. If the overall geometry is tetrahedral, then there are three possibilities for the molecular geometry; if it is trigonal planar, there are two possibilities; and if it is linear, the molecular geometry must also be linear. The diagram below illustrates the relationship between overall (electronic) and molecular geometries. To view the geometry in greater detail, simply click on that geometry in the graphic below. Although there are many, many different geometries that molecules adopt, we are only concerned with the five shown below.
Fusion occurs in the core of the sun and other stars.
The sun converts mass into energy and releases them.
There is little information present in square of element.It does not contain information about atomic radius,melting point and other properties.It does not tell about the state of element.
A change from one form of matter to another, with the release of large amounts of energy.
