The electron configuration for an element is the arrangement of electrons in the orbits (or shells) of a neutral atom. Shells closer to the nucleus have higher binding energy.
For example, there are eleven electrons in a sodium atom (atomic number 11). Scientists have measured the quantities of energy needed to remove these electrons one by one from a sodium atom. It is quite easy to remove the the first electron. The next 8 are difficult to remove. Finally, it becomes really hard to remove the last two electrons, which are held very powerully because they are the closest to the nucleus.
This is just a common representation of electron configuration.
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Example : For an atom of oxygen, there are 8 protons and 8 electrons. The first 2 electrons are in the subshell designated 1s, which can contain 2 electrons. The next 2 are in the shell designated 2s, which can also contain 2 electrons. The final 4 are in the 2p shell, which can contain up to 6 electrons. So the configuration is written as :
1s2 2s2 2p4
The ways electrons are arranged around the nuclei of atoms in various obitals are called electron configurations.
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Electronic configuration is the arrangement of electrons in the energy levels of an atom.
The electron configuration of an atom is the particular distribution of electrons among available shells
All of the representative elements (s and p block) have predictable electron configurations. However, many of the transition elements have electron configurations that are not predicted by the rules for determining electron configuration.
Group 18
halogens
The elements with the electron configurations that end in ns 2 and np 5 are halogens, group VII A elements.
The elements with the electron configurations that end in ns 2 and np 5 are halogens, group VII A elements.
Solutions are mixtures of one or more solutes dissolved in a solvent. They do not have electron configurations. Only atoms and ions have electron configurations.
All of the representative elements (s and p block) have predictable electron configurations. However, many of the transition elements have electron configurations that are not predicted by the rules for determining electron configuration.
Group 18
any time there are as many electrons and protons and they fill each orbital optimally.
The externall shell of electrons is completely filled.
The electron configuration of strontium is 1s22s22p63s23p63d104s24p65s2.
halogens
The elements with the electron configurations that end in ns 2 and np 5 are halogens, group VII A elements.
The elements with the electron configurations that end in ns 2 and np 5 are halogens, group VII A elements.
group 13 or IIIA
Each neutral atom has a specific electron cofiguration.
The electron configuration for sulfur is [Ne]3s2.3p4.The electron configuration for mercury is [Xe]4f14.5d10.6s2.