---
title: "IUPAC names of four complexes"
subject: "Engineering Chemistry"
chapter: 6
key: "semester_2/engineering_chemistry:iupac-names-2070"
source: https://www.bctengineer.com/q/semester_2/engineering_chemistry/iupac-names-2070
site: BCT Engineering
---

# IUPAC names of four complexes

Engineering Chemistry · Chapter 6: Coordination Complexes

- Asked in: 2070 Bhadra, 2 marks
- Video: [Naming Coordination Compounds - Chemistry](https://www.youtube.com/watch?v=yeNtqjE0dJw) — The Organic Chemistry Tutor
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_2/engineering_chemistry/iupac-names-2070
- Whole chapter: https://www.bctengineer.com/md/semester_2/engineering_chemistry/chapter-6

## Question

Write the IUPAC name of the following co-ordination compounds.
i) Na[Au(CN)₂]
ii) K₃[Fe(C₂O₄)₃]
iii) [PtCl₂(NH₃)₄]Br₂
iv) [Co(NH₃)₆]Cl₃

## Short answer

i) sodium dicyanoaurate(I), ii) potassium trioxalatoferrate(III), iii) tetraamminedichloroplatinum(IV) bromide, iv) hexaamminecobalt(III) chloride.

## Answer

i) Na[Au(CN)₂]: **sodium dicyanoaurate(I)**
ii) K₃[Fe(C₂O₄)₃]: **potassium trioxalatoferrate(III)**
iii) [PtCl₂(NH₃)₄]Br₂: **tetraamminedichloroplatinum(IV) bromide**
iv) [Co(NH₃)₆]Cl₃: **hexaamminecobalt(III) chloride**

Oxidation states: Au +1 (x − 2 = −1); Fe +3 (x − 6 = −3); Pt +4 (x − 2 = +2).

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is the IUPAC name of Na[Au(CN)2]?
   A. sodium dicyanogold(I)
   B. sodium dicyanoaurate(III)
   C. gold dicyanosodium
   D. sodium dicyanoaurate(I)
   Answer: D. The correct option is: sodium dicyanoaurate(I). This follows from the answer on au. (Key point: Au)

2. What is the oxidation state of Pt in [PtCl2(NH3)4]Br2?
   A. +4
   B. +2
   C. +3
   D. +6
   Answer: A. The correct option is: +4. This follows from the answer on pt. (Key point: Pt)

3. What is the IUPAC name of K3[Fe(C2O4)3]?
   A. potassium trioxalatoiron(III)
   B. potassium trioxalatoferrate(III)
   C. potassium trioxalatoferrate(II)
   D. iron potassium oxalate
   Answer: B. The correct option is: potassium trioxalatoferrate(III). This follows from the answer on fe. (Key point: Fe)

## Close variants set in other exams

- [IUPAC names of four complexes](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Aiupac-names-2070m) — Engineering Chemistry, chapter 6, asked 4×
- [IUPAC names of four complexes](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Aiupac-names-2072m) — Engineering Chemistry, chapter 6, asked 4×
- [IUPAC names of two complexes](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Aiupac-names-2069) — Engineering Chemistry, chapter 6, asked 4×

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