U2 Atomic structure and isotopes + electronic configuration

What 3 subatomic particles make up an atom.

Protons, Neutrons and Electrons

What is the nucleus of the atom?

The nucleus is most of the atoms mass, it’s incredibly dense and made from protons and neutrons and held by nuclear force.

What are the charges of the subatomic particles?

Proton - positive(+1)

Neutron - neutral(0)

Electron - negative(-1)

What are the sizes of the subatomic particles relative to a proton

Proton - 1

Neutron - 1

Electron -1/1800

Why is the nucleus dense

Protons and neutron are relatively equal mass and are huge in comparison to electrons.
This is why the nucleus is dense.

What makes up the mass of the atom

Proton and neutrons

What is an electron orbit (Bohr model)

Electrons revolve around the nucleus in fixed, circular orbits,

How does energy correlate to electron orbit

The electrons’ orbits correspond to specific energy levels in the atom.can only occupy fixed energy levels and cannot exist between two energy levels

The Bohr model suggests that electrons were grouped in

different energy levels, called electron shells. From n1 - n7, with 1 being the lowest and 7 being the discovered highest, meaning electrons have more energy. All electrons in the same shell have the same energy and therefore same spin.

Why do electrons in n1 have less energy(speed)

Because of the electrostatic attraction that is more powerful since the electrons are closer, so it takes more energy and is harder for them to move(spin) since they are bound.

How is the atom that makes up the element determined

The type of atom that makes up each element is determined by the number of protons (atomic number) in the nucleus. 

What determines the atomic number

The number of protons in the nucleus of the atom, same amount of proton = same element

What determines the mass number (weight of atom/nucleus)

The total number of protons + neutrons in the nucleus, (electrons weight is so small they don’t contribute)

What does it mean if an atom is electrically neutral

Therefore number of electrons = number of protons 

What is the equation to find the number of neutrons

Atomic mass - atomic number

All atoms that belong to the same element have the same number

of protons in the nucleus and therefore the same atomic number, Z. 

What are isotopes

Atoms that have the same number of protons (atomic number) but different numbers of neutrons (and therefore different mass numbers)

Do all elements have isotopes

All elements have isotopes even hydrogen has 3

Which isotope appears on the periodic table determining the atomic weight?

It is determined by the most abundant type of isotope in the element found in nature

What do isotopes have

identical chemical properties but different physical properties such as mass and density. In particular, some isotopes are radioactive

What does the proton determine

An atoms elemental identity, as well as the number of electrons and the atomic number

What does the electron determine

Chemical reactivity (more change = reactivity) and properties, an atoms participation in chemical reactions and change.

What does the neutron determine

The physical properties of an atom like its mass and density

What if an isotope is too big and heavy

The heaviest isotope (mass) is the most radioactive. If the nucleus gets too big, the atom can’t sustain itself this is nuclear decay, to stop the decay it’ll eject neutrons from the nucleus to be lighter changing isotopes.

What is transmutation

When subatomic particles change to avoid being ejected, a neutron will become a proton to not be ejected. This changes elemental identity such as gold = mercury.

What is electron configuration

How electrons are configured around an atom

What are the two rules for electron configuration

Rule 1. Each shell can only contain a maximum number of electrons.

Rule 2. Lower energy shells fill before higher energy shells.

What is the formula for how many electrons a shell can hold

n-2n², n1 - 2, n2 - 8, n3 - 18, n4 - 32

How does electron configuration work for the first 20 elements

If its the 19 or 20 element, n3 only goes up to 8 and then you start on the fourth shell. From n4 upwards for the first 20 elements N2, 3 and 4 all hold 8 except for n1.

What is valence

The outermost electrons and shell

What are the patterns in electronic configuration

Same group have the same amount of valence electrons in valence shell this matches the group number. Same periods have the same number of shells.