Electronic Structure and Energy Levels | GCSE Chemistry
Electrons orbit the nucleus in specific energy levels or shells.
How many electrons can fit into the first shell of an atom?
What is Electronic Structure and Energy Levels | GCSE Chemistry?
"The arrangement of electrons in the energy levels of an atom."
What is the charge of a proton?
Who provided the evidence to show that neutrons exist in the nucleus?
What did the alpha particle scattering experiment prove?
Which two subatomic particles are found in the nucleus of an atom?
Shell Rules
First shell: Maximum 2 electrons.
Second/Third shells: Maximum 8 electrons.
Group number: Equals the number of electrons in the outer shell.
Period number: Equals the number of energy levels (shells).
Mapping Rule: The electronic structure of Oxygen ($8 e^-$) is 2,6. Always check the atomic number!
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