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1. What does the percentage abundance mean? How does a mass spectrometer work? Someone please help me, I dont understand this
2. (Original post by Love123443)
What does the percentage abundance mean? How does a mass spectrometer work? Someone please help me, I dont understand this
Okay, hold on a sec XD Do you have a specific question e.g for homework or whatever that you need to answer or you just want to understand about mass spectroscopy?
(Original post by Blake Jones)
Okay, hold on a sec XD Do you have a specific question e.g for homework or whatever that you need to answer or you just want to understand about mass spectroscopy?
4. (Original post by Love123443)
Okay, give me a sec to write it out but I'll give you an explanation type summary
5. (Original post by Love123443)
What does the percentage abundance mean? How does a mass spectrometer work? Someone please help me, I dont understand this
A mass spectrometer is the piece of equipment used in mass spectrometry. Mass spectrometers measure the atomic of molecular mass of atoms or molecules in a sample. Mass spectrometers also tell you how much there is of each one (they call this abundance). If all of your sample is one element they can tell you the relative abundance (how much there is) of each isotope so you'll know what proportions of each isotope there are.

In a mass spectrometer all particles are ionised so they have a +1 charge (usually +1). These are called cations. The ions are separated in the spectrometer depending on their mass to charge ratio. Mass to charge ratio is basically their mass divided by their charge. In most cases the charge is 1 and so they are sorted by mass as anything divided by 1 is itself.

The separate ions are then detected by their mass and an abundance can be given for each one.
6. Thankyou so much, I understand it now x
(Original post by Blake Jones)
A mass spectrometer is the piece of equipment used in mass spectrometry. Mass spectrometers measure the atomic of molecular mass of atoms or molecules in a sample. Mass spectrometers also tell you how much there is of each one (they call this abundance). If all of your sample is one element they can tell you the relative abundance (how much there is) of each isotope so you'll know what proportions of each isotope there are.

In a mass spectrometer all particles are ionised so they have a +1 charge (usually +1). These are called cations. The ions are separated in the spectrometer depending on their mass to charge ratio. Mass to charge ratio is basically their mass divided by their charge. In most cases the charge is 1 and so they are sorted by mass as anything divided by 1 is itself.

The separate ions are then detected by their mass and an abundance can be given for each one.
7. (Original post by Love123443)
Thankyou so much, I understand it now x
No worries, anytime

Do you know why chlorine has the atomic mass of 35.5?

Well the percentage abundance is just the abundance of the isotope as a percentage. Chlorine is found naturally in the atmosphere in two isotopes (there may be more but they're so small that we don't count them). 75% of chlorine naturally found is of the isotope Cl-35.

That means 0.75*35 = 26.25
0.25*37 = 9.25

As for mass spectrometry, you don't need to heavily know how this works...

https://www2.chemistry.msu.edu/facul...c/masspec1.htm

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