TOF Flashcards
What happens in stage 1 of ionisation for low Mr elements?
Has to be a gas state. An electron gun has to fire high energy electrons to knock off 1 electron to turn it into a positive ion.
What happens at stage 1 of ionisation for high Mr compounds?
For a solution. A needle fires high voltage and gains a proton. Therefore forms a fine mist because they are all positive so repel each other.
What happens at stage 2 of acceleration?
The particles all have the same ke but don’t travel at the same speed because of their mass.
What happens at stage 4 detection?
positive ions hit a negative plate
The electrons move from the plate to the ion
This produces an electric current
The size of current is proportional to abundance of each isotope.
What happens at the mass spectrum electrospray
Gains an electron
How do you find the mass of 1 mole of positive ion of your element?
Divide by 1000 to convert it into kg
Then divide by avogrado constant to find the mass of 1 ion
Equation for speed
Ke =1/2 X mass X vˆ2
What is the equation of speed?
Speed = distance/time
what is the Aufaba principle ?
It states that the lowest energy sub-levels are occupied first because electrons are attracted to the positive nucleus.
What is the exception to the normal rules of orbital filling ?
Chromium and Copper
What is the Pauli exclusion principle?
It states that each orbital may contain no more than 2 electrons.
What is the Hunds rule?
It states that single electrons occupy all empty orbitals within a sub-level before they start to form pairs in orbitals. Two electrons in the same orbital then theres a repulsion between them due to their negative charges. The most stable configuration is with single electrons in different orbitals.
