![]() |
Creado por Bethany Westwood
hace casi 8 años
|
|
Pregunta | Respuesta |
Mass of: Proton Neutron Electron | Proton: 1 Neutron: 1 Electron: 1/1840 |
Charge of: Proton Neutron Electron | Proton: +1 Neutron: 0 Electron: -1 |
Nucleons | Particles in the nucleus of an atom |
What are nucleons held together by? What does this cause? | Held together by strong nuclear force Releases large amounts of energy during nuclear fission |
Ion | Atom that looses or gains electrons |
What is a mass spectrometer? | Most useful instrument to accurately measure RAM and amount of each isotope |
Which is the only atom with an isotope with an RAM that's an even number? Why is this? | Carbon-12 Neither protons or neutrons have a mass of exactly 1 |
What does a mass spectrometer do? | Measures the mass of separate atoms |
When is mass spectrometry used in real life? | By forensic scientists to identify different substances |
How do mass spectrometers separate different isotopes? | Separate ions by mass:charge ratio |
What are the 4 stages in a Time of flight (TOF) mass spectrometer? | Ionisation Acceleration Ion drift Detection |
What condition does a TOF spectrometer have to be in? Why? | A Vacuum To prevent ions colliding with molecules in the air |
What happens during the Ionisation stage in a TOF mass spectrometer? (Electrospray ionisation) | Electrospray ionisation: sample dissolved in volatile substance :Forced through fine needle :To a positive terminal of high voltage :Tiny +charged droplets :Solvent evaporates until single positively charged ion is produced |
What happens during the Ionisation stage in a TOF mass spectrometer? (Electron impact) | :Sample vaporised :High energy electrons fired from electron gun :Knocks off 1 electron from each electron forming a 1+ ion |
What is an electron gun made from? | hot wire filament with a current running through it |
What happens in the acceleration stage in a TOF mass spectrometer? | +ions are attracted to a -plate and accelerate towards it Lighter and higher charged ions accelerate faster |
What happens in the ion drift stage in a TOF mass spectrometer? | :Ions pass through hole in -charged plate :Forms a beam :Travel along a flight tube :To the detector |
What happens in the detection stage in a TOF mass spectrometer? | :Ions of same charge arrive at detector :Flight times recorded :+ions pick up electron from detector :current flows |
What is an isotope? | an atom of the same element with the same number of protons and electrons but a different number of neutrons |
What is a principal quantum number? | The amount of orbitals (shells) an atom has. |
What is the Heisenberg uncertainty principle? | You can't know where an electron is and its speed and direction |
What shapes are the orbitals? | s- sphere d - dumbbell p - various f - various |
What can each orbital contain? | 2 electrons in an opposite spin |
What are electrons? | Cloud of charge/wave |
What is different about the electron configuration of copper and chromium? | Steal from 4s to make 3d |
Why do sub-levels overlap? | As you get further from the nucleus, principal energy levels get closer together |
How do electrons move levels? | They are promoted to a higher level by quanta which is a packet of energy |
What happens when electrons come back down from promotion? | A photon is released which produces colour |
Why can zinc not be promoted? | It has a full 3d sub shell |
What is 1st ionisation energy? | Energy required to remove an electron from the outer shell of one mole of atoms in their gaseous state |
What is the affect of Charge on nucleus on IE? | :More protons :Higher charge :More energy needed to remove electron :Higher IE |
What is the affect of distance of electron from nucleus on IE? | :Bigger distance :Lower attraction :Less energy needed :Lower ionisation energy |
What is the affect of amount of shielding between outer electrons and nucleus on IE? | :More quantum levels :More shielding :Less energy needed :Lower ionisation energy |
¿Quieres crear tus propias Fichas gratiscon GoConqr? Más información.