Atomic Structure And Bonding Flashcards
Occupied shells tell us the
Period number
Number of valence electrons tells us the
Group number
What is an electron cloud
A region of space where there is a probability of an electron being found
Emission spectra and the atom
-When an element is heated, electrons absorb energy and can be ‘promoted’ to higher energy state (excited state)
-When element relapses from excited state to lower energy state (ground state), energy is released as electromagnetic radiation which we see as colour
Bohr model of the atom
-electron in a given orbit has a constant energy t/f called ‘energy shells’
-electrons can only occupy fixed energy levels and cannot exist between two levels
-empty orbits have fixed energy levels
-orbits of larger radii have more energy
-there are sub-shells to each major level
If a shell is not occupied, it still exists. True or False?
True
How many electrons can s sub-shell hold
2 electrons
How many electrons can p sub-shell hold
6
How many electrons can d sub-shell hold
10
How many electrons can f sub-shell hold
What is an orbital?
A region of space in which up to two electrons may be located
How many orbitals in s sub-shell
1
How many orbitals in p sub-shell
3
How many orbitals in d-subshell
5
How many orbitals in f sub-shell
7
S sub-shell
-Lowest energy subshell in every electron shell
- one orbital
-spherical shape
P sub-shell
-three orbitals
-can hold up to 6 electrons in total
D subshell
-contains 5 different orbitals
-can hold up to 10 electrons
-third shell is first to contain d sub-shell
F subshell
-start at fourth energy level
-7 different orbitals
-can hold up to 14 electrons
Subshell defintion
A specific energy level within an electron shell. Designated s,p,d,f in order of increasing energy
Pauli exclusion principle
States only a maximum of two electrons may be found in a given atomic orbital, and that if an orbital is filled, the electrons will have opposite spin
Aufbau principle
States that subshells are filled in order from lowest to highest energy and a lower energy subshell will be completely filled before electrons move into higher energy sub-shell
Hunds rule
States that electrons in a partially filled subshell will arrange themselves to form maximum number of half-filled orbitals
-singles before doubles