Atomic Strucutre And IE Flashcards
What is the atomic number?
Number of protons in the nucleus of an atom
What is the mass number?
The sum of the number of protons and neutrons in the nucleus of an atom (protons + neutrons)
Define isotopes
Atoms of the same element that have the same atomic number but different mass numbers
What is relative atomic mass (Ar)?
Average mass of the isotopes of an element compared to 1/12th of the mass of a carbon-12 atom
What is molecular mass (Mr)?
Sum of relative atomic masses of the atoms in a molecule
What is the role of an ionisation chamber in mass spectrometry?
To form positive ions from the sample
What is the purpose of the electron gun in a mass spectrometer?
To provide high energy electrons that collide with the sample’s atoms or molecules
Fill in the blank: The positive ions are accelerated by an _______ field.
Electric
What happens when positive ions enter the magnetic field in a mass spectrometer?
They get deflected based on their mass-to-charge ratio
True or False: Ions with the same charge will have the same deflection in a magnetic field.
False
What is detected on the metallic plate in a mass spectrometer?
Deflected ions that pass through a narrow slit
What happens to the strength of the magnetic field in mass spectrometry?
It is changed to detect positive ions with other mass-to-charge ratios
Fill in the blank: An ion with m/z ratio of 28 and charge 1 will be detected at the same time as an ion with m/z ratio of 28 and charge _______.
2
What is the maximum number of electrons in the first quantum shell?
2
The formula for the maximum number of electrons per shell is 2n², where n is the principal quantum number.
What is the maximum number of electrons in the second quantum shell?
8
Calculated using the formula 2(2) = 8.
What is the maximum number of electrons in the third quantum shell?
18
Calculated using the formula 2(3) = 18.
What is the maximum number of electrons in the fourth quantum shell?
32
Calculated using the formula 2(4) = 32.
What is Hund’s rule?
Electrons occupy the orbit singly before doubly.
##Footnote
Minimizes electron electron repulsion
What is the Pauli Exclusion Principle?
Two electrons cannot occupy the same orbital unless they have opposite spins.
What is ionization energy?
The energy required to remove an electron from one mole of gaseous atom of an element to form one mole of gaseous +1 ion.
True or False: Ionization energy is an exothermic process.
False
Ionization energy is an endothermic process.
What factors affect ionization energy?
- Atomic Radius
- Nuclear Charge
- Electron Shielding
- Subshell Energy Levels
Atomic radius x IE
Distance between e and nucleus ⬆️ nuclear attraction ⬇️ IE ⬇️
Shielding x IE
Inner shell electrons repeat outer shell electrons so ⬇️ nuclear attraction and IE
