Mass spectrometry

Question 1

how does mass spectrometry work

Answer 1

It measures the mass to charge ratio of molecules

Question 2

every atom has a

Answer 2

unique proton and electron number

Question 3

NMR

Answer 3

atomic resolution data
slow
limited for mixtures
0.1-5mg

Question 4

mass spectrometry

Answer 4

molecule resolution
fast
mixtures and pure compounds
single molecule ng/pg

Question 5

mass spec uses

Answer 5

historical
biological

Question 6

mass spec can show

Answer 6

isotopic abundancy

Question 7

the effects of isotopes is

Answer 7

addictive

Question 8

the bigger the molecule the

Answer 8

greater the effect of isotopes will have

Question 9

accurate mass

Answer 9

mass of principle isotope
monisotopic

Question 10

soft ionisation

Answer 10

too light not enough energy
no fragmentation

Question 11

hard ionisation

Answer 11

fragmentation

Question 12

electron ionisation

Answer 12

hard
Pi systems
beam of e- wavelength close to the wavelength of the bond
it interfers with the electrons in the bond, causing a lose of an e-

Question 13

chemical ionisation

Answer 13

the reagent undergoes electron ionisation.
the reagent gas collides with the sample which transfers
a proton to the sample.

Question 14

electrospray ionisation

Answer 14

sample is added with ionic compound.
pass through fine capillary needle
needle is attach high voltage at a high potential.
the solution is aerosol.
solution droplet enter a vaccuum.
the solvent evaporates
columbic explosion, the like ions repel each other

Question 15

quadrople mass analyser

Answer 15

scientist controls the rod via DC voltage.
only desired ion pass through rods.
other ions are neutralised by rod

Question 16

TOF

Answer 16

Accelerated by electric field.
ionic drift
detectation

Question 17

ch4, ch3ch3, etc for m+ 1 peak

Answer 17

the percentage of isotope doubles, 1.1, then 2.2 etc.

Question 18

how to find number of carbons?

Answer 18

peak/highest peak * 100/percentage of isotope abundancy

Question 19

how to find if a molecule has a double bond?

Answer 19

carbon number - h/2 + n/2 , + 1

if it is an integer then there is a high chance.

Question 20

within electronic energy levels

Answer 20

there will be vibrational energy

Question 21

within vibrational energy levels

Answer 21

there will be rotational energies

Question 22

transition between e energy levels occur with

Answer 22

x rays

Question 23

transition between v energy levels happen in

Answer 23

IR