Sulfur, phosphorus, silicon, and chlorine
are common examples of elements that form an expanded octet. Phosphorus pentachloride (PCl
5
) and sulfur hexafluoride (SF
6
) are examples of molecules that deviate from the octet rule
Can you have more than 8 valence electron?
octet rule: Atoms lose, gain, or share electrons in order to have a full valence shell of eight electrons.
Hydrogen
is an exception because it can hold a maximum of two electrons in its valence level.
What is an atom with 8 valence electrons called?
The
octet rule
is a chemical rule of thumb that reflects the theory that main-group elements tend to bond in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble gas.
Why is the maximum number of valence electrons 8?
The number of valence electrons in any atom of a Representative Element corresponds to its Group Number. … As all Group VIII members have a filled valence shell,
they have no tendency to react in oxidation-reduction reactions
.
Which of the following atoms can have more than 8 outermost electrons when it forms a covalent bond?
Answer: Only
atoms with empty d orbital
can achieve more than 8 electrons in a covalent bond. The electronic configuration of sulphur in ground state is [Ne]3s2 3p4. In this state it has two unpaired electron so it can make only two bonds.
Why is 3rd shell 8 or 18?
Each shell can contain only a fixed number of electrons, up to two electrons can hold the first shell, up to eight (2 + 6) electrons can hold the second shell, up to
18 (2 + 6 + 10)
can hold the third shell and so on. The general formula is that the nth shell can hold up to 2(n
2
) electrons in principle.
Why can Xenon have more than 8 valence electrons?
Xe does not follow the octet rule. It actually bonds. … Xenon having
valence electrons in the 4th energy level, will also have access to the 4d sublevel
, thus allowing for more than 8 electrons.
How many valence electrons does group 13 have?
126 Atoms and Bonding Page 4 Each element in Periods 2 and 3 has one more valence electron than the element to its left. Group 1 elements have 1. Group 2 elements have 2. Group 13 elements have
3 valence electrons
.
Why are there only 8 electrons in the outer shell?
This is due to
the quantum nature of the atoms
, where electrons are arranged into shells: there are 2 electrons in the first called the K shell, 8 in the second (L-shell), 18 in the third (M shell). …
Why do electrons want a full outer shell?
Atoms want a full outer shell
because it completes all the gaps in the outside
. With no gaps, other electrons don’t want to fit into those spaces. For example, a noble gas like Neon has a full outer shell. It doesn’t react with other chemicals because the electrons from other chemicals can’t fall in anywhere.
Which group has the most valence electrons?
Elements with the most valence electrons are in
group 18
.
Why is it important to have 8 electrons?
The Significance of “8” in Chemistry
The rule of 8 or the Octet rule is the
tendency of atoms to have eight electrons in their valence shell
. Eight electrons in this final shell allow atoms to be stable and non-reactive. … Atoms tend to be reactive when their valence shell (or outermost shell) is incomplete.
What can hold up to 8 electrons?
The electrons like to be in separate shells/orbitals. Shell number one can only hold 2 electrons, shell two can hold 8, and for
the first eighteen elements shell three
can hold a maximum of eight electrons.
When forming covalent bonds which atom can have more than 8 valence electrons?
Due to presence of vacant d-orbital excitation occurs in
Cl-atom
and it can have more than eight valence electrons when it is forming hypervalent compound like HClO4.
In which compound Covalency of nitrogen is 4?
Now
ammonia
donates this lone pair of electrons to form one coordinate covalent bond with a proton and forms ammonium ion (NH4+). So, we have seen that N can form 4 bonds in total (3 covalent bonds and 1 co-ordinate bond). And so the covalency of N will be 4.
Which follows octet rule?
Elements that obey octet rules are main group elements which are
oxygen, carbon, nitrogen
. s-block and p-block elements obey octet rule except for hydrogen, helium, and lithium.
