Which atoms can be hypervalent?

Which atoms can be hypervalent?

Phosphorus pentachloride (PCl5), sulfur hexafluoride (SF6), chlorine trifluoride (ClF3), and the triiodide ion (I3−) are examples of hypervalent molecules. For the elements in the second period of the periodic table (principal energy level n=2), the s2p6 electrons comprise the octet, and no d sublevel exists.

What can be the central atom?

The central atom is usually the atom with the lowest subscript in the molecular formula and the atom that can form the most bonds. If all of the atoms usually form the same number of bonds, the least electronegative atom is usually the central atom. Hydrogen can only make one bond!

Which atoms are exceptions to the octet rule?

However, there are three general exceptions to the octet rule: Molecules, such as NO, with an odd number of electrons; Molecules in which one or more atoms possess more than eight electrons, such as SF6; and. Molecules such as BCl3, in which one or more atoms possess less than eight electrons.

What is a hypervalent atom?

A hypervalent molecule may be defined as a molecule in which there are more than four pairs of electrons around the central atom in the conventional Lewis diagram of the molecule.

Is ClO4 is hypervalent?

– Hypervalent molecule is a molecule that contains one or more main group elements apparently bearing more than eight electrons in their valence shells. Therefore, (PO4)3-, (SO4)2-, (ClO4)- are hypervalent compounds.

What are hypervalent species?

The most common exceptions to the octet rule are the so-called hypervalent compounds. These are species in which there are more atoms attached to a central atom than can be accommodated by an octet of electrons.

Which is hypervalent?

From Wikipedia, the free encyclopedia. A hypervalent molecule (the phenomenon is sometimes colloquially known as expanded octet) is a molecule that contains one or more main group elements apparently bearing more than eight electrons in their valence shells.

What is meant by Hypervalent?

What is central atom with example?

For example, oxygen is the central atom in H2O (water), and carbon is the central atom in CO2 (carbon dioxide).

Which of the following elements can not form Hypervalent molecules select all that apply?

Elements in the third and higher periods (n≥3) have more than four valence orbitals and can share more than four pairs of electrons with other atoms because they have empty d orbitals in the same shell. Therefore, of the elements listed above boron and nitrogen can not form hypervalent molecules.

What is hypervalent compound example?

What are hypervalent compounds?

Key Points Main group elements that form more bonds than would be predicted by the octet rule are called hypervalent compounds, and have what is known as an ‘expanded octet,’ meaning that there are more than eight electrons around one atom.

Does hypervalence of a chemical bond depend on d-orbital involvement?

Indeed, quantum mechanical theories of the chemical bond do not need to invoke d -orbital involvement. These theories suggest that hypervalence is probably no more than a consequence of the greater radii of the atoms of period-3 elements compared with those of period 2, with the result that a central atom can pack more atoms around itself.

Is hypervalence a steric or orbital problem?

Thus, hypervalence is more a steric (geometric) problem than an outcome of d -orbital availability. How six atoms can be bonded to a central atom by fewer than six pairs of electrons is discussed below. Less common than hypervalent compounds, but by no means rare, are species in which an atom does not achieve an octet of electrons.

What is the debate over the nature and classification of hypervalent molecules?

The debate over the nature and classification of hypervalent molecules goes back to Gilbert N. Lewis and Irving Langmuir and the debate over the nature of the chemical bond in the 1920s. Lewis maintained the importance of the two-center two-electron (2c-2e) bond in describing hypervalence, thus using expanded octets to account for such molecules.