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Electron orbitals

Although useful to explain the reactivity and chemical bonding of certain elements, the Bohr model of the atom does not accurately reflect how electrons are spatially distributed surrounding the nucleus. They do not circle the nucleus like the earth orbits the sun, but are found in electron orbitals . These relatively complex shapes result from the fact that electrons behave not just like particles, but also like waves. Mathematical equations from quantum mechanics known as wave functions can predict within a certain level of probability where an electron might be at any given time. The area where an electron is most likely to be found is called its orbital.

Recall that the Bohr model depicts an atom’s electron shell configuration. Within each electron shell are subshells, and each subshell has a specified number of orbitals containing electrons. While it is impossible to calculate exactly where an electron is located, scientists know that it is most probably located within its orbital path. Subshells are designated by the letter s, p , d , and f . The s subshell is spherical in shape and has one orbital. Principal shell 1n has only a single s orbital, which can hold two electrons. Principal shell 2n has one s and one p subshell, and can hold a total of eight electrons. The p subshell has three dumbbell-shaped orbitals, as illustrated in [link] . Subshells d and f have more complex shapes and contain five and seven orbitals, respectively. These are not shown in the illustration. Principal shell 3n has s , p , and d subshells and can hold 18 electrons. Principal shell 4n has s , p , d and f orbitals and can hold 32 electrons. Moving away from the nucleus, the number of electrons and orbitals found in the energy levels increases. Progressing from one atom to the next in the periodic table, the electron structure can be worked out by fitting an extra electron into the next available orbital.

Illustration shows 1ns, 2ns and 2np subshells. The 1ns subshell and 2ns subshells are both spheres, but the 2ns sphere is larger than the 1ns sphere. The 2np subshell is made up of three dumbbells that radiate out from the center of the atom.
The s subshells are shaped like spheres. Both the 1n and 2n principal shells have an s orbital, but the size of the sphere is larger in the 2n orbital. Each sphere is a single orbital. p subshells are made up of three dumbbell-shaped orbitals. Principal shell 2n has a p subshell, but shell 1 does not.

The closest orbital to the nucleus, called the 1s orbital, can hold up to two electrons. This orbital is equivalent to the innermost electron shell of the Bohr model of the atom. It is called the 1 s orbital because it is spherical around the nucleus. The 1 s orbital is the closest orbital to the nucleus, and it is always filled first, before any other orbital can be filled. Hydrogen has one electron; therefore, it has only one spot within the 1 s orbital occupied. This is designated as 1 s 1 , where the superscripted 1 refers to the one electron within the 1 s orbital. Helium has two electrons; therefore, it can completely fill the 1 s orbital with its two electrons. This is designated as 1 s 2 , referring to the two electrons of helium in the 1 s orbital. On the periodic table [link] , hydrogen and helium are the only two elements in the first row (period); this is because they only have electrons in their first shell, the 1 s orbital. Hydrogen and helium are the only two elements that have the 1 s and no other electron orbitals in the electrically neutral state.

Questions & Answers

what is reproduction
mana Reply
reproduction is the process by which living organisms give rise to young ones of their own kind
What is evolution
the production of new forms of life over time as documented in the fossil record.
give two parasites where secondary host is water snail?
Kevin Reply
what is treats
Raih Reply
what are the organelles in cell that involves in protein sythenis
Rita Reply
what is a melanin?
Judith Reply
what is telophase
melanin in that black color we posse in our skins
Why do parasites take on a parasitic life?
Asadullah Reply
what is cell
Ousman Reply
A cell is the basic structure unit of an organ
what is respiration
what is organisms?
Organisms are living things that can function on their own
A cell is a functional basic unit of an organisms.
Organisms is a entity which consists of one or more cells and are able to undergo all life processes
A respiration is the physical and chemical break down of complex food substance into absorbable or simple form.
What will to a cell if the nucleus is removed..?
Goodrick Reply
When a cell nucleus removed then the cell will not be able to function properly, it will not be able to grow .All the metabolic functioning of the cell will stop .Without nucleus the cell will lose it's control. It can not carry out cellular reproduction .
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write a short note on how the kidney carry out osmoregulation in man
Rhoda Reply
Kidney play a very large role in human osoregulation by regulating the amount of water reabsorbed from glomerular filtrate in kidney as tubules, which is controlled by hormones such as antrdiuvetic hormone (ADH) , aldosterone and angiotensin.
kidney is capable of osmoregulation in mammal ,
simple definition for respiratory system
Gift Reply
Respiratory system is a network of organs and tissues that helps you to breathe or help in getting the rids of oxygen and discharge of carbon dioxide in the body.
What are uses of respiratory system
how it functions
what is inresparetion
Why do parasites take on a parasitic life?
A respiratory system is a biological system consisting of specific organs and structures used for gas exchange in animals and plant
diseases of respiration
when air enters to the body called inresparetion
explain why plants responds to stimuli slowly than animals
how is a aerenchyma tissue adapted to its function
fatuma Reply
Have large air spaces that store air for gaseous exchange... Large air spaces also facilitate bouyancy.
what does DNA mean
innocent Reply
dioxiribo nucleic acid
Deoxyribonucleic acid
dioxide nucleic acid
what does RNA mean
Ribonucleic acid
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defin work of DNA
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Victor Reply
zygote is developed or fertilized egg cell
what is the difference between cell wall and cell membrane
Ruhiyatu Reply
cell wall is found in plant while cell membrane is found in animal cell
please this is the main answer to that question okay Cell wall gives shape and support to the cell whiles Cell membrane support the movement of substances into and out of the cell. This question is very tricky that's why I asked.
cell wall makes the cell turgid,in times of flaccidity while cell membrane is a semi permeable tissue
how cell I form
Elijah Reply

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