How many shells does an atom have

Examples: NaCl,KBr,etc. Begin typing your search term above and press enter to search. Press ESC to cancel. Skip to content Home Physics How many shells can an atom have? Ben Davis September 5, How many shells can an atom have? What is the overall charge of the atom?

What are electrons used for today? How does an electron move? What are 2 or more elements chemically combined? An atom with one or two valence electrons more than a closed shell is highly reactive, because the extra valence electrons are easily removed to form a positive ion.

An atom with one or two valence electrons fewer than a closed shell is also highly reactive, because of a tendency either to gain the missing valence electrons thereby forming a negative ion , or to share valence electrons thereby forming a covalent bond. Like an electron in an inner shell, a valence electron has the ability to absorb or release energy in the form of a photon. An energy gain can trigger an electron to move jump to an outer shell; this is known as atomic excitation.

Or the electron can even break free from its associated atom's valence shell; this is ionization to form a positive ion. When an electron loses energy thereby causing a photon to be emitted , then it can move to an inner shell which is not fully occupied. The number of valence electrons of an element can be determined by the periodic table group vertical column in which the element is categorized.

With the exception of groups 3—12 the transition metals , the units digit of the group number identifies how many valence electrons are associated with a neutral atom of an element listed under that particular column. Introduction What more could we want to know about the structure of an atom?

Shells An electron shell may be thought of as an orbit followed by electrons around an atom nucleus. Valence Electrons The valence shell is the outermost shell of an atom in its uncombined state, which contains the electrons most likely to account for the nature of any reactions involving the atom and of the bonding interactions it has with other atoms.

The n number determines how many of the subshells make up the shell. For example, the 1st shell is made up of 1 subshell, s. It can therefore contain only 2 electrons. The 2nd shell is made up of 2 subshells, s and p. As an example, Lithium has 3 electrons. You can see this by looking at the atomic number of Ca on a. The first 2 go in shell 1, leaving 18 more.

Then there are 2 left. Like we said, Ca has 20 electrons. But Ca- has 21, and Ca2- has Lets say we take Helium, which has 2 electrons. These 2 electrons will be just enough to fill Shell 1.

If I give them some more energy, one of those electrons jumps up to Shell 2. But as soon as it can, this electron will fall back to Shell 1 again.

When it does, it will release energy as light. Hope this answers your question! I am lost when you say like 2S and 2P and I know that they are called subshells. But what does subshell really mean? Does it mean that eg. I really want to know and thank you. Rather, the state is a wavelike cloud spread around the nucleus. For S-type states, the cloud has a perfectly spherical shape.