Scientists
This scientist is who provided evidence for the existence of the electron.
J.J Thomson were the first to provide evidence for the existence of the electron, a negatively charged subatomic particle.
Quantum (wave) mechanical model
How many Quantum Numbers are there? Name them.
There are 4 Quantum Numbers:
1. Principal Quantum Number
2. Angular Momentum (secondary) Quantum Number
3. Magnetic Quantum Number
4. Spin Quantum Number
What is an orbital?
An orbital is the region around the nucleus where an electron has a high probability of being found.
What are 3 ways that electron configuration can be shown?
1. Energy Level Diagrams
2. Complete Electron Configuration
3. Condensed Electron Configuration
This scientist introduced the concept of the Wave Particle Duality.
Louis De Broglie - what is matter (electrons) had wave-like properties
What replaced Bohr Theory?
Bohr Theory was replaced by Quantum Mechanics.
The principal quantum number (n) in the quantum model represents this.
The principal quantum number (n) describes the size & energy of an orbital (e.g. n = 1,2,3,... to ∞)
This type of orbital is described as having a dumbell shape.
P orbitals have a dumbell shape & exist in sets of three (px, py & pz).
What is the complete & condensed configuration for chlorine?
complete - 1s22s22p63s23p5
condensed - [Ne] 3s23p5
He formulated the famous equation E=nhf, which relates the energy of a photon to frequency.
Max Planck
In quantum mechanics, this term is the mathematical probability of finding an electron in a certain region of space.
Wave function is the mathematical probability of finding an electron in a certain region of space.
What are the letters used to describe the secondary quantum number (l)?
The secondary quantum number (l), describes the shape of an atomic orbital.
l = 0: s (sharp)
l = 1: p (principal)
l = 2: d (diffuse)
l = 3: f (fundamental)
l = 4: g
What are the 4 types of orbitals? How many electrons can each hold?
There are 4 main types of orbitals:
s - 2 electrons
p - 6 electrons
d - 10 electrons
f - 14 electrons
What is [Kr] 5s24d105p3.
Antimony.
This scientists developed the first successful atomic model to incorporate quantum theory.
Niels Bohr, he introduced a model of the atom with electrons orbiting the nucleus in quantized energy levels, this is called the Bohr model.
What is Heisenberg's Uncertainy Principle?
Heisenberg's Uncertainy Principle is the idea that it is impossible to know the exact position and speed of an electron at a given time.
Explain the Pauli Exclusion Principle.
The Pauli Exclusion Principle states that in a given atom, no two electrons in the same atom can be in the same set of four quantum numbers (n, l, ml, ms).
These orbitals have no nodes & are spherically symmetric around the nucleus.
s orbitals have no nodes (except the spherical node present in higher energy s orbitals) & are spherically symmetric.
Write the electron configuration for bromine.
bromine - 1s22s22p63s23p64s23d104p5
What are the differences between the old and new theories?
Old:
1. Electrons can move between different orbitals by absorbing/emitting quanta of energy
2. Orbitals
New:
1. Electrons act like particles & waves
2. The location of an electron is given by a probability distribution
3. Orbitals
What are the two main ideas of the quantum mechanical model?
The two main ideas of the quantum mechanical model are that electrons can move between orbitals by absorbing or emitting quanta of energy, and that the location of electrons is given by a probability distribution.
List all the possible quantum numbers for an 2s orbital.
n = 2
l = 0
ml = 0
ms = +1/2 -1/2
Explain the differences between Orbitals & Orbits.
Orbitals:
- 2 electrons
- three dimensions
- distance from nucleus varies
- no set path
Orbits
- 2n2 electrons
- two dimensions
- path is elliptical or circular
Describe the Aufbau Principle.
The Aufbau Principle states that electrons occupy the lowest energy orbitals available before filling higher energy orbitals.
- The # of electrons in an atom is equal to the atomic number
- When adding electrons to orbitals, start by filling the orbital with the lowest energy & work your way up
- Remember each orbital can have a maximum of 2 electrons