AAMC #10 bio question

[HotHamH2O]

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Question 117 asks, "What participant in the electron transport chain has the greatest attraction to electrons."
A) FAD
B) NAD+
C) Oxygen
D) Cytochrome C

Obviously the answer is oxygen because oxygen is the final electron acceptor in electron transport but I was wondering if someone can explain to me why it's not technically a proton acceptor since it is accepting H+. Isn't oxygen electron rich with it's two lone pairs and it's -2 charge therefore actually accepting protons 2H+. Can anyone explain why it termed "electron acceptor"?

 

[MedGrl@2022]

Question 117 asks, "What participant in the electron transport chain has the greatest attraction to electrons."
A) FAD
B) NAD+
C) Oxygen
D) Cytochrome C

Obviously the answer is oxygen because oxygen is the final electron acceptor in electron transport but I was wondering if someone can explain to me why it's not technically a proton acceptor since it is accepting H+. Isn't oxygen electron rich with it's two lone pairs and it's -2 charge therefore actually accepting protons 2H+. Can anyone explain why it termed "electron acceptor"?

Oxygen is more electronegative... 2nd most electronegative element... next to flourine

 

[HotHamH2O]

Oxygen is more electronegative... 2nd most electronegative element... next to flourine

right...but why is taking up protons 2H+ termed "electron accepting"?

 

[Postictal Raiden]

Question 117 asks, "What participant in the electron transport chain has the greatest attraction to electrons."
A) FAD
B) NAD+
C) Oxygen
D) Cytochrome C

Obviously the answer is oxygen because oxygen is the final electron acceptor in electron transport but I was wondering if someone can explain to me why it's not technically a proton acceptor since it is accepting H+. Isn't oxygen electron rich with it's two lone pairs and it's -2 charge therefore actually accepting protons 2H+. Can anyone explain why it termed "electron acceptor"?

Molecular oxygen has a total charge of zero. By accepting electrons, molecular oxygen becomes oxygen ion and now it can donate its electron (acting as lewis base) and accept two protons (acting as bronsted base) to form water.

 

[HotHamH2O]

ahhh...this explains it. http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__electron_transport_system_and_atp_synthesis__quiz_1_.html

the electrons come from H being oxidized into H+ and the electrons are transfered from cytochrome C to 1/2O2 and which combines with 2H+ protons and water is formed.

 

[HotHamH2O]

Molecular oxygen has a total charge of zero. By accepting electrons, molecular oxygen becomes oxygen ion and now it can donate its electron (acting as lewis base) and accept two protons (acting as bronsted base) to form water.

thank you. that makes sense. I was thinking 0 and not 1/2 02