In this I/GCSE Chemistry blog post, we will be looking at the electronic structure of different atoms.
Electronic structures
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Electrons are arranged around the nucleus in shells or energy levels.
- The lowest energy level is shown by the shell that is nearest to the nucleus.
- The electrons in an atom occupy the lowest available energy level.
An energy level can only hold a certain number of electrons.
- The shell nearest to the nucleus can only hold two electrons.
- The second energy level can hold up to eight electrons.
- Once there are eight electrons in the third energy level, the fourth begins to fill up.
You can write the number of electrons in each energy level (electronic structure).
- Start at the first shell.
- Record the numbers in each successive shell.
- The number of electrons in each shell are separated from each other by a comma.
Any one of the elements of the main groups of the periodic table have the same number of electrons in their outermost shell. They are called the outer electrons.
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The chemical properties of an element depends on how many electrons it has.
An element's reactivity is determined by the number of electrons it has in its outermost shell.
- Because elements in a particular group have the same number of electrons in its outermost shell, they all react similarly.
The elements in Group 0 of the periodic table are called noble gases.
- They are very unreactive because they have a stable arrangement of electrons with eight electrons in their outermost shell
- except for helium which has two electrons in the outer shell.
That is all!
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References:
https://www.google.com/url?sa=i&url=https%3A%2F%2Flearn.sparkfun.com%2Ftutorials%2Fwhat-is-electricity%2Fflowing-charges&psig=AOvVaw3wD_ykDEcOISZr3gT2H5zW&ust=1628150090161000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCKi-pvLxlvICFQAAAAAdAAAAABAD
https://www.google.com/url?sa=i&url=https%3A%2F%2Fcourses.lumenlearning.com%2Fboundless-chemistry%2Fchapter%2Felectron-configuration%2F&psig=AOvVaw0mqOcEv0jP6ibDOQqz5v8C&ust=1628150141735000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCPi3konylvICFQAAAAAdAAAAABAD