MAE 3324 CH2 Flashcards
Why should you have a solid knowledge of interatomic bonding in solids?
In some instances, the type of bond allows us to explain the properties of a material.
The atomic number is the number of…
Protons in the nucleus.
Atoms are separated on the PT by?
Atomic number
For an electrically neutral atom, what is the relationship between the atomic number and the number of electrons?
They’re the same number.
Define “Atomic Mass.”
The sum of the masses of protons and neutrons within the nucleus.
In an isotope, the number of _____ may vary.
Neutrons
Define “Atomic weight.”
The weighted average of all the atomic masses of all the naturally occurring isotopes.
Define 1 amu.
1/12 of the atomic mass of the most common isotope of carbon which is carbon 12.
What is avagodros number?
The number of atoms in one mole of material. 6.022E23 atoms/mole
.
Is amu/atom any different than grams/mole?
No, they’re the same thing.
Define “Quantum mechanics.”
A set of principles and laws that govern systems of atomic and subatomic entities.
What is mean by the saying “Electrons are quantized?”
They can only hold a certain amount of energy.
During a quantum jump, when an electron absorbs energy, it transitions to a _____ energy state.
higher
During a quantum jump, when an electron emits energy, it transitions to a _____ energy state.
lower
In the wave mechanical model, an electron is considered to exhibit what two characteristics simultaneously?
The electron behaves as both a wave and a particle simultaneously.
In the wave mechanical model, the position of the electron is described by what?
A probability distribution or “electron cloud.”
Shells are specified by?
A principal quantum number n, which may take on integral values beginning with unity (one).
How many electrons can fit in the 1s shell?
2
How many electrons can fill the 2s shell?
2
How many electrons can fill the 2p shell?
6
How many electrons can fill the 3s shell?
2
How many electrons can fill the 3p shell?
6
How many electrons can fill the 3d shell?
10
The first quantum number is related to what physical aspect of the atom?
The electrons average distance from the nucleus.
What does the second quantum number designate?
The subshell.
Name the values for the quantum number L and their subshell designations.
0 = s 1 = p 2 = d 3 = f
Electron orbital shapes depend on what quantum number?
L
The s orbitals are in the shape of?
Spheres.
The third quantum number stipulates what?
The number of electron orbitals for each subshell.
Extra Notes: This value is also referred to as the magnetic number.
The third quantum number is also called what?
The magnetic number.
When L=0, m_L can only have a value of what? This corresponds to what subshell?
Zero. This corresponds to an S subshell with only one orbital.
If L =1, what values can m_L take on, and what orbitals are possible?
M_L could be -1, 0, or 1
Three p orbitals are possible (px, py, and pz).