Time of flight mass spectrometer

Question 1

How is the sampled prepared?

Answer 1

gaseous/aqueous sample is added to the machine

heater vaporises all solutions/liquids into gases

Question 2

How is the particle accelerated?

Answer 2

it needs to be ionised, using electrospray ionisation, using high voltage electricity to knock off electrons,

so the atoms become positively charged

negatively charged plates attract the ions and accelerated them to high speeds

Question 3

What is ion drift?

Answer 3

all the ions travel at a constant speed, however ions can be distinguished as the heavier an ion is, the slower it moves

accelerated to the same kinetic energy, therefore ones with the larger mass have a smaller velocity

Question 4

What happens as the sample hits the detector plate?

Answer 4

an electric current is formed to create a spectrum read out the ions pick up an electron from the detector

which causes a current to flow passed through a computer to form a mass spectrum

Question 5

What conditions are needed inside a mass spectrometer?

Answer 5

Complete vacuum to prevent ions colliding with air

Question 6

Why must the sample be ionised?

Answer 6

to deflect the beam

only ions create a current when hitting the detector

Question 7

State what can be adjusted in the mass spectrometer to enable ions formed by the different isotopes to be directed onto the detector

Answer 7

accelerating potential

Question 8

What are ions deflected usinng?

Answer 8

magnetic field