Atomic Structure Flashcards
What charge does a Proton have?
1.6 x 10^-19 C
What charge does a Electron have?
-1.6 X 10^-19 C
What mass does a Proton and Neutron have?
1.67 x 10^-27 kg
What mass does an Electron have?
9.1 x 10^-31 kg
What’s the number of Protons called?
Atomic number
What letter represents the Atomic number?
Z
What 2 names represents the number of protons and neutrons in an atom?
Nucleons
The atomic mass
What letter represents the atomic mass number?
A
An element with a specific number of protons and neutrons is called what?
A Nuclide
What’s an Isotope?
Elements with the same number of protons but different number of neutrons
Give an example of an Isotope
Deuterium which is an isotope of Hydrogen
What’s an Isobar?
Nuclides with the atomic mass but different atomic number
How does nuclei containing multiple protons (positive charges) stay together?
The strong force (Nuclear binding energy)
What 2 things does the Nuclear binding energy represent?
The exact amount of energy required by the strong force to hold the nucleus together
The amount of energy required to break the strong force and allow the protons to escape the nucleus
What’s the Mass defect?
The entire nucleus weighs slightly less than the sum of its nucleons
How is the nucleus kept stable?
Neutrons
What is the ratio of the number of protons to the number of neutrons in lighter nuclei?
1 : 1 ratio
What is the ratio of the number of protons to the number of neutrons in heavier nuclei?
1 : 1.5 ratio
What are unstable nuclides called?
Radionuclides
What are unstable isotopes called?
Radioisotopes
How do unstable nuclei become lighter and more stable?
By giving off energy in the form of radiation
List the first 4 shell letters
K
L
M
N
How do you calculate the maximum number of electrons a shell can hold?
2n^2
n = shell no.
How many electrons does the M shell hold?
18
Where do electrons hold a greater potential energy?
The further away they are from the nucleus
How do electrons move up an energy level?
Gaining energy
How do electrons move down an energy level?
losing energy
What exists between the positive nucleus and the negative electron shells?
Electrostatic attraction
What is electron binding energy?
The minimum amount of energy that is required to remove an electron from an atom
What 2 things affect electron binding energy?
Shell level
Number of protons
When the electrons are all in the correct shell, the atom is said to be?
At Ground state
When an electron gains energy it can rise to a slightly higher energy state. What’s this called?
Excitation
How does an electron escape from an atom?
When the electron receives enough energy to match the electron binding energy
When an electron escapes from an atom, what’s this called?
Ionisation
The downward movement of electrons moving into lower shells releases energy in what 2 ways?
Characteristic radiation
Auger electrons
What does Characteristic radiation equal?
Difference in binding energy between the two shell levels
What is an Auger electron?
When an electron receives enough energy it is released from the atom causing an electron to drop down to the lower shell to fill the vacancy. This releases energy which could then hit another electon causing it to escape the atom as an auger electron (If the energy is high enough).
What’s an Ion?
An atom which has lost an electron
