1.1 Atomic Structure (part 1) Flashcards
What subatomic particles are atoms made up of
Protons, neutrons and electrons
What is the charge, mass and location of a proton?
Charge: +1
Mass: 1
Location: nucleus
What is the charge, mass and location of a neutron?
Mass: 1
Charge: 0
Location: nucleus
What is the charge, mass and location of an electron?
Mass: 1/2000
Charge: -1
Location: shells
Atomic number definition
Number of protons in the nucleus of an atom
Mass number definition
Number of protons and neutrons in the nucleus of an atom
Isotope
Atoms of the same element with a different number of neutrons
Why do isotopes have the same chemical properties?
Same no of elections> same electron configuration> dictates chemical behaviour
What is formed when an atom loses electrons
Positively charged ion (cation)
What is formed what an atom gains electrons?
A negative ion (anion)
What is mass spectrometry used for?
Determining information about elements and compounds, it can be used to calculate relative atomic mass of an electrons or relative molecular mass of a compound
What are the four stages of mass spectrometry
- ionisation
- acceleration
- separation of ions
- detection
What two methods of ionisation are there
Electron impact and electrospray ionisation
What are the 3 stages of electron impact ionisation
- sample injected into spectrometer and vaporised
- high energy electrons from electron gun fired at sample
- high energy electrons knock off an electron from each particle to form positive ions
What would the equation be if gaseous sodium was ionised by electron impact ionisation
Na (g) -> Na+ + e-
What are the 4 stages of electrospray ionisation?
- sample dissolved in polar solvent
- injected through a fine hypodermic needle to give a fine mist
- tip of needle is attached to the positive terminal of a high voltage supply
- particles gain a proton (H+ ion) from the solvent to form positive ions