Electronic Structure Flashcards
Atomic Structure and the Periodic Table (15 cards)
What do electrons always occupy?
Shells
Electrons occupy specific energy levels known as shells.
What are the lowest energy levels in an atom?
The ones closest to the nucleus
These levels are filled first according to the Electron Shell Rules.
How many electrons can the first shell hold?
2
This is the maximum capacity of the first shell.
How many electrons can the second shell hold?
8
The second shell can hold up to 8 electrons.
How many electrons can the third shell hold?
8
The third shell also can hold a maximum of 8 electrons.
Why are atoms happier?
When they have full electron shells
Atoms tend to be more stable when their outer shells are filled, similar to noble gases.
What is the electronic structure configuration for sodium?
2, 8, 1
This configuration represents the distribution of electrons in sodium’s shells.
What is the atomic number of nitrogen?
7
The atomic number indicates the number of protons and electrons in a neutral atom.
What is the electronic structure of nitrogen?
2, 5
The first shell has 2 electrons, and the second shell has 5 electrons.
What is the atomic number of magnesium?
12
This means magnesium has 12 protons and 12 electrons.
What is the electronic structure of magnesium?
2, 8, 2
The first shell has 2 electrons, the second shell has 8 electrons, and the third shell has 2 electrons.
Fill in the blank: The electronic structure for helium is _______.
2
Helium has a full first shell with 2 electrons.
What is the electronic structure for calcium?
2, 8, 8, 2
This shows the distribution of electrons across the shells of calcium.
True or False: The third shell can only be partially filled.
False
The third shell can hold up to 18 electrons but is commonly filled to 8 in many elements.
What is the electron configuration for carbon?
2, 4
Carbon has 2 electrons in the first shell and 4 in the second shell.
