Determination of oxidation numbers in caffeine

Click For Summary

Discussion Overview

The discussion revolves around determining the oxidation numbers of carbon and nitrogen in caffeine (C8H10N4O2), focusing on the challenges posed by its molecular structure and the application of oxidation number rules.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant notes that the oxidation numbers of oxygen and hydrogen are -2 and +1, respectively, but questions how to determine the oxidation numbers of carbon and nitrogen.
  • Another participant states that the structure of the molecule is essential for assigning oxidation numbers to carbon atoms, indicating that the molecular formula alone is insufficient.
  • A subsequent reply suggests a method for calculating the oxidation number of carbon based on the number of bonds to oxygen or nitrogen minus the number of bonds to hydrogen.
  • It is mentioned that oxidation numbers are merely accounting devices for balancing redox reactions and do not represent measurable properties of atoms.

Areas of Agreement / Disagreement

Participants generally agree on the importance of molecular structure in determining oxidation numbers, but there is no consensus on a definitive method for calculating the oxidation numbers of carbon and nitrogen in caffeine.

Contextual Notes

The discussion highlights the limitations of using a molecular formula to assign oxidation numbers and the dependence on structural information, which remains unresolved.

mcfaker
Messages
43
Reaction score
0
Hi,
The formula of caffeine is C8H10N4O2. The oxidation numbers of O & H are -2 & +1 according to the book. How do I determine the oxidation numbers of C or N.

Note: The substance is a molecular substance so we cannot apply the following rule: "the oxidation number of an atom in a monatomic ion is the charge of the monatomic ion"

How do I determine the oxidation numbers of C or N? Can someone please help me out?


Thanks in advance!
 
Physics news on Phys.org
It depends on the structure - there is no way of assigning ON to carbon atoms just by looking at the molecular formula.
 
Thanks, so could you please explain how it would be possible to determine those oxidation numbers?
 
You can calculate an oxidation number for a carbon atom as equal to the number of bonds to O, N (or halogen) minus the number of bonds to H.

Please note ON don't reflect any real (measurable) property of an atom, they are just accounting device used to balance redox reactions. Don't treat them too seriously.
 
Ok Thanks for the help, They are just a hypothetical charge.
 

Similar threads

Oxidation Numbers for H3AsO4 and H2S Equation
  • · Replies 5 ·
Replies
5
Views
2K
Chemistry How do we interpret the steps in the algorithm to balance a redox equation?
  • · Replies 7 ·
Replies
7
Views
3K
Can Methane and Citric Acid be Balanced in a Redox Reaction?
  • · Replies 3 ·
Replies
3
Views
2K
Electropositivity - 2nd opinion needed
  • · Replies 1 ·
Replies
1
Views
2K
Oxidation Numbers: Confusion with Electronegativity
  • · Replies 10 ·
Replies
10
Views
12K
Oxidation state and chiral configurations
  • · Replies 4 ·
Replies
4
Views
2K
What are the oxidation numbers for each element in these compounds and ions?
  • · Replies 3 ·
Replies
3
Views
3K
Calculate Caffeine Molecular Formula: C8H10N4O2
  • · Replies 2 ·
Replies
2
Views
5K
Determining Oxidation Numbers of KClO3, NH4+, Cr2O72-, MnO42-
  • · Replies 5 ·
Replies
5
Views
2K
Stability of Sulfides: Lewis Acid-Base Covalent Bonding
  • · Replies 1 ·
Replies
1
Views
3K