Atomic Models, Quantum Numbers, Orbital Diagram, Rules, Magnetic Properties, ,

Question 1

What model and by who

• the scientist drew upon the ancient greek idea of atoms (greek word - atomos - indivisible)
• all matter is made of atoms, which are indivisible (cannot be divided)
• all atoms of a given element are identical in mass and properties.
• compounds are combinations of two or more different types of atoms.

limitations: atoms are not indivisible, they are composed of subatomic particles

Answer 1

solid sphere model by john dalton

Question 2

What model and by who

• depicts the electrons as negatively-charged particles (plum) embedded in a sea of positive charge. (pudding)

limitations: no nucleus

Answer 2

plum pudding model by J.J. Thomson

Question 3

What model and by who

• the first atomic model to feature a nucleus at its core
• In the nuclear atom, the protons and neutrons, which comprise nearly all of the mass of the atom, are located in the nucleus at the center of the atom. The electrons are distributed around the nucleus and occupy most of the volume of the atom.
• this was discovered by the scientist by firing positively charged alpha particles on a sheet of gold foil (most passed through and some deflected - only possible if the atom is mostly empty space, w/ nucleus concentrated on the center)

limitations: did not explain why electrons remain in orbit around the nucleus

Answer 3

nuclear model by Ernest Rutherford

Question 4

What model and by who

• modified Rutherford’s model of the atom by stating that electrons moved around (orbit) the nucleus in orbits of fixed size with energies
• electron energy was quantised; electrons could not occupy values of energy between the fixed energy levels (limited to certain specific energy values)

limitations: moving electrons should emit energy and collapse into the nucleus, did not work well for heavier atoms

Answer 4

planetary model by Niels Bohr

Question 5

What model and by who

• stated that electrons do not move in set paths around the nucleus, but in waves
• it is impossible to know the exact location of the electrons; instead, we have clouds of probability called orbitals, in which we are more likely to find an electron
• widely accepted and most accurate

Answer 5

quantum/electron cloud model by erwin schrodinger

Question 6

States that is impossible to know both the accurate position and velocity of an electron or any given particle simultaneously.

Answer 6

Heisenberg Uncertainty Principle (Werner Heisenberg)

Question 6

States that matter also has properties
associated with waves. (quantum mechanical model treats electrons as waves)

Answer 6

Quantum Theory by Louis de Broglie

Question 7

Planetary model vs. electron cloud model

Answer 7

• planetary model - stationary paths or orbits, certain in the location of electron
• electron cloud model - 3d regions/locations, predicts the location of an electron

Question 8

every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and all electrons in singly occupied orbitals have the same spin.

Answer 8

Hund’s Rule (by Friedrich Hund)

Question 9

• From the German Aufbauprinzip, “to build” (also called the building up principle)
• states that in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available
  energy levels before occupying higher levels.

Answer 9

Aufbau Principle

Question 10

• No two electrons in the same orbital orientation
  can have the same spin.
• With only one spin up and one spin down, the
  maximum number of electrons that can fit into
  any given orbital orientation is two.

Answer 10

Pauli Exclusion’s Principle (by Wolfgang Pauli)

Question 11

sublevels - number of orbitals - total number of electrons in sublevel - shape

Answer 11

s - 1 - 2 - sphere
p - 3 - 6 - dumbbell/peanut
d - 5 - 10 - cloverleaf/double peanut
f - 7 - 14 - diffused/flower

Question 12

Quantum Number

• describes the energy of an electron and the most probable distance of the electron from the nucleus.
• energy level
• pertains to the size of the orbital

Answer 12

Principal Quantum Number (n)

• 1, 2, 3, …, 7

Question 12

space around the nucleus in which
the electron is found ( a three-dimensional description of the most likely location of an electron around an atom.)

Answer 12

orbital

Question 13

Quantum Number

• describes the general shape or region an electron occupies—its orbital shape.
• orbital space

Answer 13

angular momentum/azimuthal (l)

• 0, 1, 2, 3

Question 14

Quantum Number
- describes the orbital orientation in space

Answer 14

magnetic quantum number (m sub l)

• -3, …, 3

Question 15

Quantum Number
- the direction the electron is spinning in a magnetic field.

Answer 15

spin quantum number (m sub s)

• -1/2 +1/2

Question 16

each energy level can contain at most ___ electrons

Answer 16

2n squared

Question 17

It is the distribution of electrons
of an atom or molecule in atomic or
molecular orbitals.

Answer 17

electron configuration

Question 18

longhand configuration vs. shorthand configuration

Answer 18

longhand - 1s-7f
shorthand - with use of noble gases

Question 18

longhand configuration vs. shorthand configuration

Answer 18

longhand - 1s-7f
shorthand - with use of noble gases

Question 19

symbolic notation

Answer 19

superscript - atomic mass
subscript - atomic number (no. of p; if it is a neutral atom - no. of p = no. of e)

Question 20

a property of any material that responds to an applied magnetic field.
- can be either paramagnetic, diamagnetic or ferromagnetic depending on their reaction to the presence of a magnetic field.
- can be known based on its electronic configuration.

Answer 20

magnetism

Question 20

a kind of magnetism that is associated with iron, cobalt, nickel, and some alloys or compounds containing one or more of these elements. (also gadolinium)
- any material that could exhibit spontaneous magnetization
- the strongest and most familiar type of
magnetism being exhibited by permanent magnets.
- attracted to both the north and south poles of a magnet

Answer 20

ferromagnetism

Question 21

exhibit a weak attraction towards magnets. They still pull themselves toward magnets, but paramagnetic materials are much weaker than ferromagnetic materials.
- will only pull themselves towards one pole
- If an atom has one or more unpaired electrons, it
is said to be this. The unpaired electrons
are attracted by a magnetic field due to the
electrons’ magnetic dipole moments ( the magnetic moment of an electron resulting from its intrinsic properties of spin and electric charge.)

Answer 21

paramagnetism

Question 22

repel magnets. They don’t exhibit any attraction to magnets.
- characterized by paired electrons or no unpaired
electrons causing the magnetic fields of the electrons to cancel out. Thus, the atom has no net
magnetic moment and so it repels a magnetic
field.

Answer 22

diamagnetic