Flashcards
Mass Spectroscopy
Flashcards do conjunto (10)
- 1What is mass spectroscopy?- use of experimental data to calculate the relative atomic mass of a sample.
- 2What does mass spectroscopy allow us to do?- accurately determine the relative atomic mass of a sample
- 3What is the definition of relative atomic mass?- the mean mass of all the isotopes of an atom relative to the mass of 1/12 of one atom of 12C.
- 4Why is the sample kept in a vacuum during this process?- to prevent ions from colliding with molecules in the air
- 5What happens during the ionisation stage of mass spectroscopy?- sample is dissolved into a volatile solvent
- forced through a positively charged (by positive terminal of high voltage supply)
- tiny positive droplets get smaller as they separate during evaporation
- positively charged sample is then accelerated by an electric field - 6What happens during the acceleration stage of mass spectroscopy?- positive ions in the sample are attracted towards a negatively charged plate
- lighter/ highly charged ions travel fastest - 7What happens during the ion drift stage of mass spectroscopy?- ions pass through a hole and form a beam before travelling along the flight tube
- 8What happens during the detection stage of mass spectroscopy?- lighter ions arrive first at a high velocity
- flight times are recorded
- positive ions have picked up an electrons
- positive ions collide with the detector and cause a current to flow - 9What happens at the data analysis stage of mass spectroscopy?- signal from detector is pass to a computer to generate a mass spectrum
- 10What is the equation for finding the relative atomic mass from a mass spectroscopy table?combined mass of all isotopes
-----------------------------------------
combined abundance of all isotopes
Informações
- Descrição
- A level Chemistry FlashCards sobre Mass Spectroscopy, criado por Caitlyn Randles em 28-09-2017.
- Criado por
- Caitlyn Randles
- Visualizações
- 1
- Avaliação