Deduce the oxidation state of nitrogen in N₂O.

Each oxygen is −2 and the molecule is neutral, so each nitrogen is +1.

Why is the name nitrate(V) used in preference to nitrate?

The Roman numeral states the oxidation state of nitrogen, distinguishing NO₃⁻ from the nitrate(III) ion, NO₂⁻.

OCR A-Level Chemistry B H433

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The Chemical Industry

Oxidation states of nitrogen and the tests for nitrate and ammonium

4 things to know
Components 01, 02 and 03

Overview

Recall questions on the oxidation state of nitrogen in its oxides and ions, and the Devarda's alloy and hydroxide tests.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Numbers

What are the oxidation states of nitrogen in NO and NO₂, why is 3NO₂ + H₂O → 2HNO₃ + NO a disproportionation, and which stage of S + O₂ → SO₂ then 2SO₂ + O₂ ⇌ 2SO₃ is an equilibrium?

Key term

Why are all four N-H bonds in the ammonium ion identical, and what is the oxidation state of nitrogen in N₂O and NO₂?

Key term

What are the oxidation states of nitrogen in the nitrate(V) ion, the nitrate(III) ion and the ammonium ion?

Numbers

Nitrogen monoxide is oxidised by 2NO + O₂ → 2NO₂. Give the oxidation state of nitrogen in each oxide.

Questions from this subtopic

Each one with the model answer underneath.

1
Deduce the oxidation state of nitrogen in N₂O.
Model answer
Each oxygen is −2 and the molecule is neutral, so each nitrogen is +1.
2
Deduce the oxidation state of nitrogen in NO₂.
Model answer
Nitrogen is +4.
3
Deduce the oxidation state of nitrogen in the nitrate(V) ion.
Model answer
Nitrogen is +5 in NO₃⁻.
4
Deduce the oxidation state of nitrogen in the nitrate(III) ion.
Model answer
Nitrogen is +3 in NO₂⁻.
5
Deduce the oxidation state of nitrogen in the ammonium ion.
Model answer
Nitrogen is −3 in NH₄⁺.
6
Why is the name nitrate(V) used in preference to nitrate?
Model answer
The Roman numeral states the oxidation state of nitrogen, distinguishing NO₃⁻ from the nitrate(III) ion, NO₂⁻.

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A3 ⁴₂He → ¹²₆C.

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Nitrogen is +2 in NO and +4 in NO₂.

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