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

# IUPAC names of four complexes

Engineering Chemistry · Chapter 6: Coordination Complexes

- Asked in: 2070 Magh, 0.5×4 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-2070m
- Whole chapter: https://www.bctengineer.com/md/semester_2/engineering_chemistry/chapter-6

## Question

Write IUPAC name of the following co-ordination compounds
i) [Fe(H₂O)₆]SO₄
ii) Na₃[Al(C₂O₄)₃]
iii) K₃[AlF₆]
iv) [PtCl(NO₂)(NH₃)₂]

## Short answer

i) hexaaquairon(II) sulfate, ii) sodium trioxalatoaluminate(III), iii) potassium hexafluoroaluminate(III), iv) diamminechloronitrito-N-platinum(II).

## Answer

i) [Fe(H₂O)₆]SO₄: **hexaaquairon(II) sulfate**
ii) Na₃[Al(C₂O₄)₃]: **sodium trioxalatoaluminate(III)**
iii) K₃[AlF₆]: **potassium hexafluoroaluminate(III)**
iv) [PtCl(NO₂)(NH₃)₂]: **diamminechloronitrito-N-platinum(II)** (also written diamminechloronitroplatinum(II))

Ligands are listed in alphabetical order (ammine, chloro, nitro), and the charge on Pt is +2 because Cl⁻ and NO₂⁻ together give −2 on a neutral complex.

## Check yourself

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

1. What is the IUPAC name of [Fe(H2O)6]SO4?
   A. hexaaquairon(III) sulfate
   B. hexaquaferrate(II) sulfate
   C. hexaaquairon(II) sulfate
   D. iron hexaaqua sulphate(II)
   Answer: C. The correct option is: hexaaquairon(II) sulfate. This follows from the answer on fe. (Key point: Fe)

2. What is the IUPAC name of K3[AlF6]?
   A. potassium hexafluoroaluminium(III)
   B. potassium hexafluoroaluminate(II)
   C. aluminium potassium fluoride
   D. potassium hexafluoroaluminate(III)
   Answer: D. The correct option is: potassium hexafluoroaluminate(III). This follows from the answer on al. (Key point: Al)

3. In what order are ligands listed in the name [PtCl(NO2)(NH3)2]?
   A. alphabetical (ammine, chloro, nitro)
   B. by charge
   C. reverse
   D. by size
   Answer: A. The correct option is: alphabetical (ammine, chloro, nitro). This follows from the answer on order. (Key point: Order)

4. What is the oxidation state of Pt in the neutral [PtCl(NO2)(NH3)2]?
   A. +1
   B. +2
   C. +4
   D. 0
   Answer: B. The correct option is: +2. This follows from the answer on pt. (Key point: Pt)

## Close variants set in other exams

- [IUPAC names of four complexes](https://www.bctengineer.com/question.md?key=semester_2%2Fengineering_chemistry%3Aiupac-names-2070) — 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×

## Related in Engineering Chemistry

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