M2 - Atomic Structure & Electron Structure Flashcards
Atomic structure and isotopes
What is the shape of a p-orbital?
Dumbbell / figure eight
Explain the rule of orbitals filling in order of increasing energy
1s is filled first.
For n=2 shell, filling order is: 2s, 2p
For n=3 shell, filling order is 3s, 3p, 3d
Explain the rule of orbitals with the same energy are occupied singly first
Within a sub shell, the orbitals have the same energy. One electron occupies each orbital before pairing begins. This prevents repulsion until no unoccupied orbitals remain.
Explain why isotopes have the same chemical properties (1)
Same number of electrons in the outer shell / same electron configuration
What can an electron be thought of as?
A negative-charge cloud with the shape of the orbital, called an electron cloud.
What happens in terms of energy sub-shells when forming ions?
The highest energy sub-shells lose or gain electrons.
What are the rules of orbital fillings?
Orbitals fill in order of increasing energy.
Electrons pair with opposite spins.
Orbitals with the same energy are occupied singly first.
Do isotopes react differently?
No, because chemical reactions involve electrons, not neutrons.
How can electron configuration be shortened?
1s2 can be expressed as [He].
1s2 2s2 2p6 can be expressed as [Ne].
1s2 2s2 2p6 3s2 3p6 can be expressed as [Ar].
What charge does a neutron have?
0
It is neutral
What is the charge of an electron?
-1
What does atomic number represent?
The number of protons.
How could the fraction of the isotopes of carbon be found experimentally in the lab? (1)
Mass spectrometry
What is relative atomic mass?
The weighted mean mass of an atom of an element relative to 1/12th of the mass of an atom of carbon-12.
Explain the rule of electrons pair with opposite spins
Electrons are negatively charged and repel one another.
Electrons can have spin up or spin down.
If electrons have opposite spin, the charge repulsion is counteracted enough for both to be in the orbital.
What are shells made up of?
Subshells and Atomic orbitals
Define relative isotopic mass (2)
Mass of the isotope compared to 1/12th of the mass of a carbon 12
What is the shape of an s-orbital?
Spherical
Shells are also regarded as what?
Energy levels
How many orbitals does each type contain?
S - one
P - three
D - five
F - seven
What happens to energy as the shell number increases?
Energy increases
What are isotopes?
Atoms of the same element with the same number of protons but with different numbers of neutrons.
How are electrons arranged?
In shells around the nucleus
Where does the electrons filling subshells in energy level order rule cause confusion?
The 3d sub-shell has higher energy than the 4s.
So the 4s fills before the 3d.
What are the different sub shells? How many orbitals and electrons do they have?
S-subshell- 1 orbital - 2 electrons
P-subshell- 3 orbitals- 6 electrons
D-subshell- 5 orbitals- 10 electrons
F-orbitals- 7 orbitals- 14 electrons
B
55%
1s subhell =2
3p orbital = 2
third shell = 18
What makes up the nucleus?
Protons and neutrons
What subatomic particle occupies the region around the nucleus?
Electrons
Why do atoms have no overall charge?
The same number of electrons and protons so the charges cancel out.
How many electrons can be held in an orbital?
One or two, no more.
What is the shell number referred to as?
Principal quantum number
A
What is relative isotopic mass?
The weighted mean mass of an isotope relative to 1/12th of the mass of an atom of carbon-12.
Define relative atomic mass (3)
The weighted mean mass of an atom relative to 1/12th the mass of one atom of carbon 12
What does mass number represent?
The number of protons and neutrons.
Define isotopes (1)
Atoms of an element with the same number of protons but a different number of neutrons
How many electrons can be held in each orbital type?
S - two
P - six
D - ten
F - fourteen
What is the charge of a proton?
+1
How are percentage abundances of the isotopes in a sample of an element found?
Experimentally using a mass spectrometer.
What is the electron configuration for Chromium (Cr)? (1)
1s2 2s2 2p6 3s2 3p6 4s1 3d5
What is the electron configuration of Copper (Cu)? (1)
1s2 2s2 2p6 3s2 3p6 4s1 3d10
