TOPIC 1: ATOMIC STRUCTURE & THE PERIODIC TABLE Flashcards
Mass Number
the total number of protons and neutrons in the nucleus
Atomic (proton) number
number of protons in the nucleus
Isotope
Atoms of the same element with the same number of protons but different number of neutrons.
Describe the Chemical Properties of an Isotope compared to the Element
The chemical properties of an isotope are the same as the element as they have the same electron configuration
Describe the Physical Properties of an Isotope compared to the Element
The physical properties are slightly different compared to the element as they have different mass numbers
Relative Isotopic mass
The mass of an atom of an isotope compared with 1/twelfth the mass of a carbon-12 atom
Relative Atomic Mass
The average mass of an atom compared to 1/twelfth the mass of a Carbon-12 atom
The Relative Molecular Mass (when is it used)
Used for simple molecules
Define Relative Molecular Mass
The average mass of a molecule compared to 1/twelfth the mass of a carbon-12 atom
Define Relative Formula Mass
The average mass of a formula unit compared to 1/twelfth the mass of a carbon-12 atom.
What does the Molecular ion peak tell us?
The relative mass of a compound
Maximum Number of Electrons in an S subshell
2 electrons
Maximum Number of Electrons in a P subshell
6 electrons
Maximum Number of Electrons in a D subshell
10 electrons
Maximum Number of Electrons in an F subshell
14 electrons
First Ionisation Energy
The ionisation energy is the energy needed to remove 1 mole of electrons from one mole of gaseous atoms to form one mole of positive ions.
Three Factors that effect Ionisation Energy
nuclear charge, Electron shell, Shielding
Periodicity
The repeating trend of chemical and physical properties of the elements in the periodic table
what affects atomic radius?
- Number of protons
2. Number of Shells
Isoelectronic
ions of different elements having the same number of electrons
Name giant covalent structures
- Silicon dioxide
- Diamond
- Graphite
When is the relative formula mass used
Used for ionic or giant covalent compounds
Describe the process of mass spectrometer
- Ionisation
The atom is ionised by using an electron gun that knocks off electrons giving a positive ion
- Acceleration
The ions are accelerated by an electric field so that they have all the same kinetic energy
- Deflection
The ions are then deflected by a magnetic field with the amount of deflection depending on their masses. The lighter they are the more they are deflected.
- Detection
The ions that collide with the screen are detected
What are the conditions for Mass spectrometer
- The sample must be vaporized
2. The process must be done in a vacuum to prevent other ions interfering or atoms interfering
How to work out the relative atomic mass from mass spectrometry showing relative abundances
RAM= sum of ( isotopic mass x relative abundance) / Total relative abundance
How to work out the relative atomic mass from mass spectrometry showing relative percentage abundances
RAM = sum of (isotopic mass x percentage abundance)/ 100