U1: Topic 2 Atomic orbitals Electronic configurations & periodic table Flashcards
The lowest enegry level is giving what quantum number?
n=1
What does each line on the emission spectra show?
Energy released when an electron moves between two energy levels.
What suggests that energy levels are divided into subshells?
Lines on emission spectra often made up of multiple lines.
What subshells make up each quantum number?
N=1 - s
N=2 - s,p
N=3 - s,p,d
N=4 - s,p,d,f
What is the maximum electrons for each subshell?
S - 2
P - 6
D - 10
F - 14
How are electrons considered to behave?
Both as particles and waves.
If an electron is treated as a wave the movement of the electron around the nucleus can be described how?
Mathematically
What are standing waves?
Waves that vibrate in time but do not move in space.
What is it possible to do with standing waves?
Produce a picture to create a region around the nucleus where it is most likely that the electron will be found.
Descirbe S orbitals.
Spherical. Size and energy increases as principal quantum number increases.
Describe P orbitals.
Double-lobed. 3 possible orientations in space. These degenerate orbitals lie at right angles to each other one along the all axis’s. Size and energy increase as principal quantum number increases.
Describe the D orbitals.
5 different orientations. 4 are similar 4lobed shape. all degenerate.
Describe F orbitals.
7 orientations all degenerate and complex shape.
What is the Aufbau Principle?
Orbitals filled in order of increasing energy.
What is filled first 3d or 4s and why?
4S is filled first because it has a lower energy than 3D.
What is Hund’s rule?
when degenerate orbitals are available, electrons will fill each singly with parallel spins before pairing occurs.
What is Pauli exclusion principle?
no two electrons can have the same set of four quantum numbers.
What 2 ways can you represent electronic configuration?
Orbital box notation
Spectroscopic notation
What is the principal quantum number?
Indicates the main energy level for an electron. (N) Related to size of orbital. bigger the number further away from the nucleus and more energy.
What is the Angular momentum number?
Indicates the shape the orbital resides in.
S - 0
P - 1
D - 2
F - 3
What is the magnetic quantum number?
indicates the orientation of the orbital.
What is the spin magnetic quantum number?
Indicates direction of the spin can be either -1/2 or +1/2. Orbital containing 2 electrons must have one + and one -.
What order are the quantum numbers set out?
N, L, Ml, Ms
What is ionisation energy?
energy required to remove one mole of electrons from one mole of atoms in the gaseous state.
There is a general trend of what across a period?
Increasing ionisation energy however it is not a smooth increase.
Ionisation energy provides evidence for the existence of what?
subshells which can be explained by using relative stability of certain electronic configurations.
The more stable the electronic configuration the what?
Higher the ionisation energy.
