question relating mass spectra!

[Assi1993]

hi..i dont understand why propanone and propanal have a different mass spectra though they have the same relative molecular mass..i know that they have different structure but how does that effect the spectra?

waiting for the reply !!

[Deadly_king]

hi..i dont understand why propanone and propanal have a different mass spectra though they have the same relative molecular mass..i know that they have different structure but how does that effect the spectra?

waiting for the reply !!

Am sorry I need to run for now. So I won't be able to explain. Try this though:

http://www.chemguide.co.uk/analysis/masspec/fragment.html

http://www.chemguide.co.uk/analysis/masspecmenu.html

http://www.chemguide.co.uk/analysis/masspec/howitworks.html


If you still don't understand, let me know and i'll try as much as I can to clear your doubt

[Assi1993]

Am sorry I need to run for now. So I won't be able to explain. Try this though:

http://www.chemguide.co.uk/analysis/masspec/fragment.html

http://www.chemguide.co.uk/analysis/masspecmenu.html

http://www.chemguide.co.uk/analysis/masspec/howitworks.html


If you still don't understand, let me know and i'll try as much as I can to clear your doubt

umm thanks but.....i still didnt get the answer 2 my question

[Deadly_king]

Ok......i'll try to help.

First you need to draw the structural formula of both compounds :

Propanone :CH₃COCH₃
Propanal : CH₃CH₂COH

Now we can determine the ions that will be produced during mass spectrometry.

For propanone : CH₃⁺, CH₃CO⁺ and H⁺

For propanal : CH₃⁺, CH₃CH₂⁺, CH₃CH₂CO⁺ and H⁺

NOTE : The bonds in C=O does not break since they are very strong bonds.

Since the ions formed are different, their mass spectra will surely be different  

Propanone and propanal may have the same relative molecular mass but the ions produced vary since their structure are different.

Hope it helps

[Assi1993]

Ok......i'll try to help.

First you need to draw the structural formula of both compounds :

Propanone :CH₃COCH₃
Propanal : CH₃CH₂COH

Now we can determine the ions that will be produced during mass spectrometry.

For propanone : CH₃⁺, CH₃CO⁺ and H⁺

For propanal : CH₃⁺, CH₃CH₂⁺, CH₃CH₂CO⁺ and H⁺

NOTE : The bonds in C=O does not break since they are very strong bonds.

Since the ions formed are different, their mass spectra will surely be different  

Propanone and propanal may have the same relative molecular mass but the ions produced vary since their structure are different.

Hope it helps

ohh !! Thankss!........that helped may God bless u

[Deadly_king]

ohh !! Thankss!........that helped may God bless u

You're welcome 

Thank you