Louis De Broglie
Name the theory that revolves around his work?
The Theory of Light
What are Quantum Numbers?
Integers coming from solutions to wave equations that describe specific properties of electrons in atoms.
Fill in the blank:
The quantum model is an atomic model in which electrons are treated as having ____________.
Wave characteristics.
For the quantum number n=3, what values of l are allowed, what values of ml are possible and how many orbitals are there?
n=3
l= 0 to (n-1)
=0 to 2
l= 0,1 or 2
ml= depends on l (-l to +l)
ml = -2, -1, 0, 1, or 2
Total number of orbitals= n2= (3)2=9
What can the atomic orbital of the quantum model be visualized as?
Fuzzy Cloud
What does The theory of Light suggest?
Light interacts with matter as individual particles known as photons.
What does the principle Quantum Number describe, and what is the symbol?
Indicates the energy and the relative size of atomic orbital (n).
A region in space around the nucleus that us related to a specific wave function.
What are the n, l and possible ml values for the following orbital types?
a) 2s
b) 3p
c) 5d
d) 4f
a) n=2 l=0 ml=(-l to +l) = 0
b) n=3 l=1 ml=(-l to +l)= -1, 0 or 1
c) n=5 l=2 ml=(-l to +l)= -2, -1, 0, 1, 2,
d) n=4 l=3 ml=(-l to +l)= -3, -2, -1, 0, 1, 2, 3
What does the denser regions of the model represent?
The denser regions is proportional to the probability of finding electrons at that point in the orbital. The higher the density in the orbital, the higher the probability of finding electrons.
What theory did he create ?
The Theory of Matter Waves
For the following identify the orbital letter & what does it represent:
l = 0
l = 2
l = 1
l = 3
s, d, p,f
Orbital shape within principle energy level.
What model did Quantum Models originate from?
Bohr Rutherford Diagram
What orbital type can be described by the following sets of quantum numbers?
a) n=2, l=0, ml=0
b) n=5, l=3, ml=-2
a) 2s
b) 5f
( ml does not affect orbital type)
Why is circle drawn around the nucleus in a quantum model and what does it mean?
The circle represents the "surface" of the cloud or the region where electrons spend 90% of their time and is drawn because the cloud of a quantum model has no definite boundary.
Name someone who experimentally proved his theory?
George P. Thomson
What does the variable ml represent and describe it?
Magnetic quantum number, indicates the orientation of an orbital in the space around the nucleus.
What contribution did Max Born have?
Showed the wave functions could be used to determine the probability of finding e- at any point within the region of space described by the wave functions.
The following sets of quantum numbers are not allowed. Identify the problem and change one number to give an allowed set.
a) n=1, l=2, ml=-2
b) n=4, l=1, ml=-2
a) if n=1 then l= 0 to (n-1)= 0 to (1-1)= 0; therefore l cannot be 2
but if n=3 then l= 0 to (n-1)= 0 to (3-1)= 0 to 2; therefore l can be 2 and....if l=2 then ml= -l to +l= -2, -1, 0, 1, 2 so ml can be -2
b)if n=4 then l= 0 to (n-1)= 0 to (4-1)= 0 to 3; therefore l can be 1 but...if l=1 then ml= -l to +l= -1, 0, +1 so ml cannot be -2 but can be any of the following: -1, 0 or +1
or if you change l=2 then ml= -l to +l= -2, -1, 0, 1 2 and ml= -2
Who was the physicist that proposed the Pauli Exclusion Principle and what does it state?
Wolfgang Pauli;
What is The Theory of Matter Waves?
If light waves have properties of particles then particles might have some properties of waves.
What are the allowed values for ms, and what do they represent?
+1/2 or -1/2
The quantum number that specifies the orientation of the axis on which the electron is spinning.
The Spin Quantum Number (s) has both a magnitude (1/2) and direction (+ or -).
What contribution did Werner Heisenberg have?
He mathematically showed that it is not possible to know both the position and momentum of a particle which became known has a Heisenberg uncertainty principle. This is because the mass of a electron is so small that you cannot know the position or speed of it with precision.
Label each of the following sets of quantum numbers as allowed or not allowed. Identify the problem for each of the not allowed sets.
a)n=3, l=2, ml=0
b)n=1, l=1, ml=-1
c)n=0, l=0, ml= 0
d)n=5, l=1, ml=3
a) allowed
b) not allowed; l cannot be 1 because the only allowed values for l when n=1 is 0.
c) not allowed; n can never be 0 because there is always a first energy level close to the nucleus
d) not allowed; ml cannot be 3 because ml= -l to +l and since l=1, ml can either be -1, 0 or +1
Why can only a maximum of two electrons of opposite only exist in each orbital?
A maximum of only two electrons can co-exist in an orbital because each electron exhibits different and distinctive behaviours such as orientation, shape and spin.This makes it hard for more than two electrons to exist at the same time.