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    Can som1 please explain this to me. Much appreciated
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    (Original post by YsfAli)
    Can som1 please explain this to me. Much appreciated
    How does a mass spectrometer ionise the sample?
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    (Original post by samb1234)
    How does a mass spectrometer ionise the sample?
    high voltage is applied which causes particles to lose an electron which produces positively charged ions
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    (Original post by YsfAli)
    high voltage is applied which causes particles to lose an electron which produces positively charged ions
    What would happen if it produced a 2+ charge ion?
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    (Original post by YsfAli)
    high voltage is applied which causes particles to lose an electron which produces positively charged ions
    Not quite. There is a metal coil which is emitting high speed electrons, which can essentially 'knock off' electrons in the sample making positively charged ions. What could happen if more than one of the high speed electrons collided with the sample?
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    (Original post by charco)
    What would happen if it produced a 2+ charge ion?
    2 e- knocked off
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    (Original post by samb1234)
    Not quite. There is a metal coil which is emitting high speed electrons, which can essentially 'knock off' electrons in the sample making positively charged ions. What could happen if more than one of the high speed electrons collided with the sample?
    2 electrons would be knocked off
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    (Original post by YsfAli)
    2 e- knocked off
    yes, but what would happen to the ion in the MS
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    (Original post by YsfAli)
    2 electrons would be knocked off
    So if m/z is mass to charge ratio, how would this affect the m/z value
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    (Original post by samb1234)
    So if m/z is mass to charge ratio, how would this affect the m/z value
    lighter ions hit the detector first
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    (Original post by YsfAli)
    lighter ions hit the detector first
    If i had an ion of mass 100 and charge 2+, what would be the m/z value? how can we apply that to explain the question
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    (Original post by samb1234)
    If i had an ion of mass 100 and charge 2+, what would be the m/z value? how can we apply that to explain the question
    oh okay, so the 84kr isotope loses 2 electrons would produce the peak of 42kr?
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    (Original post by YsfAli)
    oh okay, so the 84kr isotope loses 2 electrons would produce the peak of 42kr?
    yes. Because the mass would be 84, the charge would be 2+ so m/z =84/2 =42
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    (Original post by samb1234)
    yes. Because the mass would be 84, the charge would be 2+ so m/z =84/2 =42
    thanks, dont know whats wrong with me today, most prob sleep deprived
 
 
 
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