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A Chem question im confused with

4. The maxx spectrum of X2 has peaks at the following m/z values for the X +
Ion.
32, 33, 34, 35, 36
Deduce the formula of all the species responsible for each peak in the mass spectrum of X2.
Identify the element X2 and list all the isotopes present.
The mass spectrum of X2 showing peaks at m/z values of 32, 33, 34, 35, and 36 suggests that X2 is a diatomic molecule composed of an element with multiple isotopes.
1. m/z = 32: This is likely the most abundant isotope, as lower m/z values usually correspond to more abundant isotopes. Since this is a diatomic molecule (X2), each atom of X would have a mass of 16. The most common isotope with an atomic mass of 16 is 16O (Oxygen). However, Oxygen does not have isotopes that would match the other m/z values exactly, so we must consider other elements.
2. m/z = 33: This suggests an isotope of X with an atomic mass of 16.5. However, since atomic masses are integers, this peak likely represents a molecule with one atom of X being the most abundant isotope (from the m/z 32 peak) and the other being a heavier isotope.
3. m/z = 34: This could represent a molecule where both atoms are of a heavier isotope than the most abundant one. Another possibility is the presence of an isotope of X with an atomic mass of 17.
4. m/z = 35 and 36: These peaks suggest even heavier isotopes of X.
Given these considerations, a likely candidate for X is Sulphur (S), which has several isotopes that can account for the observed m/z values in the mass spectrum of S2. Sulphur's most common isotope is 32S, and it also has isotopes like 33S, 34S, and 36S, which can combine in various ways to give the observed m/z values.
Therefore, the element X is most likely Sulphur S, and the isotopes present are 32S, 33S, 34S, 36S.
(edited 1 year ago)
Original post by SilverPebble
The mass spectrum of X2 showing peaks at m/z values of 32, 33, 34, 35, and 36 suggests that X2 is a diatomic molecule composed of an element with multiple isotopes.
1. m/z = 32: This is likely the most abundant isotope, as lower m/z values usually correspond to more abundant isotopes. Since this is a diatomic molecule (X2), each atom of X would have a mass of 16. The most common isotope with an atomic mass of 16 is 16O (Oxygen). However, Oxygen does not have isotopes that would match the other m/z values exactly, so we must consider other elements.
2. m/z = 33: This suggests an isotope of X with an atomic mass of 16.5. However, since atomic masses are integers, this peak likely represents a molecule with one atom of X being the most abundant isotope (from the m/z 32 peak) and the other being a heavier isotope.
3. m/z = 34: This could represent a molecule where both atoms are of a heavier isotope than the most abundant one. Another possibility is the presence of an isotope of X with an atomic mass of 17.
4. m/z = 35 and 36: These peaks suggest even heavier isotopes of X.
Given these considerations, a likely candidate for X is Sulphur (S), which has several isotopes that can account for the observed m/z values in the mass spectrum of S2. Sulphur's most common isotope is 32S, and it also has isotopes like 33S, 34S, and 36S, which can combine in various ways to give the observed m/z values.
Therefore, the element X is most likely Sulphur S, and the isotopes present are 32S, 33S, 34S, 36S.

"Given these considerations, a likely candidate for X is Sulphur (S), which has several isotopes that can account for the observed m/z values in the mass spectrum of S2. Sulphur's most common isotope is 32S, and it also has isotopes like 33S, 34S, and 36S, which can combine in various ways to give the observed m/z values."

You cannot combine isotopes in a mass spectrum, unless they are multi atom particles. But as you are told that it is X+ then you know that this is not a multi-atom species.

Your suggestion that it is sulfur is correct and the 35S+ isotope is responsible for the peak at 35
(edited 1 year ago)
Reply 3
Original post by charco
"Given these considerations, a likely candidate for X is Sulphur (S), which has several isotopes that can account for the observed m/z values in the mass spectrum of S2. Sulphur's most common isotope is 32S, and it also has isotopes like 33S, 34S, and 36S, which can combine in various ways to give the observed m/z values."
You cannot combine isotopes in a mass spectrum, unless they are multi atom particles. But as you are told that it is X+ then you know that this is not a multi-atom species.
Your suggestion that it is sulfur is correct and the 35S+ isotope is responsible for the peak at 35

X2, it should be oxygen, no? Sulphur doesn't even exist as a diatomic molecule
Reply 4
Original post by DonnyG123
4. The maxx spectrum of X2 has peaks at the following m/z values for the X +
Ion.
32, 33, 34, 35, 36
Deduce the formula of all the species responsible for each peak in the mass spectrum of X2.
Identify the element X2 and list all the isotopes present.

Oxygen, X2, same reasons other guy said just wrong conclusion
Original post by stbons.c
X2, it should be oxygen, no? Sulphur doesn't even exist as a diatomic molecule

Sulfur is interesting.
It exists as diatomic molecules in the vapour state.
If you heat solid sulfur gently it first melts (at about 112ºC) to form a mobile orangy-yellow liquid consisting of S8 crown-shaped ring molecules.
On a little more heating these S8 crowns unravel to make S8 strings, which make the liquid viscous and red (increased London dispersion)
On further heating these break to S2 molecules that vaporise.
Original post by charco
Sulfur is interesting.
It exists as diatomic molecules in the vapour state.
If you heat solid sulfur gently it first melts (at about 112ºC) to form a mobile orangy-yellow liquid consisting of S8 crown-shaped ring molecules.
On a little more heating these S8 crowns unravel to make S8 strings, which make the liquid viscous and red (increased London dispersion)
On further heating these break to S2 molecules that vaporise.


Be that as it may, sulphur is not element X.

The question is taken from Edexcel A level chemistry June 2018 paper 1 and it should say that X2^+ forms ions with m/z values of 32 - 36, meaning the isotopes of X have relative masses of 16 - 18. X therefore cannot be sulphur and using the periodic table to look up a sensible choice of element reveals it is oxygen.
(edited 1 month ago)
Original post by TypicalNerd
Be that as it may, sulphur is not element X.
The question is taken from Edexcel A level chemistry June 2018 paper 1 and it should say that X2^+ forms ions with m/z values of 32 - 36, meaning the isotopes of X have relative masses of 16 - 18. X therefore cannot be sulphur and using the periodic table to look up a sensible choice of element reveals it is oxygen.

If the question says X2+ then it is oxygen.
That wasn't the information given in the OP.
Original post by charco
If the question says X2+ then it is oxygen.
That wasn't the information given in the OP.


Said information is given in both the question and the OP. There is a typo in the formula of the molecular ion given.
Compare it to question 2(b): https://qualifications.pearson.com/content/dam/pdf/A-Level/Chemistry/2015/Exam-materials/9CH0_01_que_20180606.pdf
Original post by TypicalNerd
Said information is given in both the question and the OP. There is a typo in the formula of the molecular ion given.
Compare it to question 2(b): https://qualifications.pearson.com/content/dam/pdf/A-Level/Chemistry/2015/Exam-materials/9CH0_01_que_20180606.pdf

The OP says: "4. The maxx spectrum of X2 has peaks at the following m/z values for the X +Ion"

It clearly says X + or I'm going blind!
Original post by TypicalNerd
Be that as it may, sulphur is not element X.
The question is taken from Edexcel A level chemistry June 2018 paper 1 and it should say that X2^+ forms ions with m/z values of 32 - 36, meaning the isotopes of X have relative masses of 16 - 18. X therefore cannot be sulphur and using the periodic table to look up a sensible choice of element reveals it is oxygen.

Still very interesting, sorry for sounding condescending if I did. Thank you.
Original post by charco
The OP says: "4. The maxx spectrum of X2 has peaks at the following m/z values for the X +Ion"
It clearly says X + or I'm going blind!

As I said - it’s a typo. Considering “mass” is also misspelt, it shouldn’t come as much surprise
Original post by charco
The OP says: "4. The maxx spectrum of X2 has peaks at the following m/z values for the X +Ion"
It clearly says X + or I'm going blind!

Mass spectrum of X2. Where X has a charge of 1+
Original post by stbons.c
Mass spectrum of X2. Where X has a charge of 1+

It should say X2^+ (again - in the OP, the question has been copied down incorrectly. This is why it is better for a photo of the question to be attached or for the copy and paste function to be used).

But yes, the fact it tells you it is a mass spectrum of X2 alone should indicate that the original question does not refer to X^+ ions, but rather X2^+.
Original post by TypicalNerd
It should say X2^+ (again - in the OP, the question has been copied down incorrectly. This is why it is better for a photo of the question to be attached or for the copy and paste function to be used).
But yes, the fact it tells you it is a mass spectrum of X2 alone should indicate that the original question does not refer to X^+ ions, but rather X2^+.

Question wasn't copied down incorrectly because I did that exact same question just yesterday, wording is right.
Original post by stbons.c
Question wasn't copied down incorrectly because I did that exact same question just yesterday, wording is right.

Even “maxx”?

There is no way the question worded correctly says “maxx spectrum”
(edited 1 month ago)
Original post by TypicalNerd
Even “maxx”?
There is no way the question worded correctly says “maxx spectrum”

IMG_0641.jpeg
I can promise you, the question should read exactly as 2(b) does here

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