Writing Formulas for Ionic Compounds

Click For Summary

Discussion Overview

The discussion revolves around the correct representation of ionic compounds formed from given ion pairs. Participants evaluate various combinations of ions and their corresponding formulas, focusing on the accuracy of charge balance and the correct stoichiometry of the resulting compounds.

Discussion Character

  • Homework-related
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Post 1 presents several ion pairs and claims to identify the correct ionic compounds they form, with specific attention to the correctness of each pairing.
  • Post 2 suggests that the charge balance is crucial for determining the correct formula, expressing uncertainty about the claim that Cu2+, O2- forms Cu2O2, proposing instead that it should be CuO.
  • Post 3 and Post 4 both express confusion about the correctness of option A, questioning the validity of O3+ as an ion.
  • Post 5 and Post 6 clarify that cuprous oxide is represented as Cu2O, while cupric oxide is CuO, indicating a misunderstanding in the original claims about copper oxides.
  • Post 7 asserts that all initial claims are incorrect, providing corrections for each ion pair and suggesting that option A contains a typographical error regarding the oxygen ion's charge.

Areas of Agreement / Disagreement

Participants express disagreement regarding the correctness of the proposed ionic compounds, with multiple competing views on how to accurately represent the compounds formed from the given ions. No consensus is reached on the validity of the original claims.

Contextual Notes

There are unresolved issues regarding the correct charges of ions and the stoichiometric ratios required for forming ionic compounds. Some participants point out potential typographical errors and misunderstandings in the original statements.

tigerwoods99
Messages
99
Reaction score
0

Homework Statement



Of the following, which correctly shows an ion pair and the ionic compound the two ions form?

Homework Equations


a. Fe3+, O3+ = Fe2O3
b. Cr3+, I- = CrI
c. Cu2+, O2- = Cu2O2
d. Sn4+, N3- = Sn4N3


The Attempt at a Solution



a. Fe3+, O3+ = Fe2O3 Incorrect
b. Cr3+, I- = CrI Incorrect
c. Cu2+, O2- = Cu2O2 Correct
d. Sn4+, N3- = Sn4N3 Incorrect

I am just wondering if that is correct? Thanks everyone!
 
Physics news on Phys.org
The key to understand #2 is to evaluate how the charges of the ions and the number of 'species' relate in the compounds. You seem to have that. I'm just not too certain about your choice #C because my best guess is that you have 1 to 1 formula ratio for cuprous oxide in the symbolically stated compound (meaning, say CuO ). My guess could very well be wrong, but I have never seen a copper compound of oxide reported as Cu2O2
 
Ah ok, so then I guess A would be correct, correct?
 
tigerwoods99 said:
Ah ok, so then I guess A would be correct, correct?

How do you justify this? What is O+3?
 
Looks like.

Note - cuprous oxide (or copper(I) oxide) would be Cu2O, CuO is cupric (or copper (II)) oxide.
 
Borek said:
Looks like.

Note - cuprous oxide (or copper(I) oxide) would be Cu2O, CuO is cupric (or copper (II)) oxide.

I was slightly confused not thinking carefully enough.
 
All look incorrect to me.

a.) O3+ should be O2-; in addition, two positive ions do not form an ionic bond.
b.) Ionic compound should be CrI3 (one Cr3+ per three I-).
c.) Ionic compound should be CuO (one Cu2+ per one O2-).
d.) Ionic compound should be Sn3N4 (three Sn4+ per four N3-).

Given the trend of b-d giving typical ions but the incorrect ionic compound, I would guess that (a) is a typo. If (a) is changed to "Fe3+, O2- = Fe2O3," then that would be correct.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 3 ·
Replies
3
Views
5K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 5 ·
Replies
5
Views
7K
Replies
5
Views
2K
  • · Replies 5 ·
Replies
5
Views
4K