Question

Рассмотрите уравнения реакций разбавленной и концентрированной азотной кислоты с медью с точки зрения процессов окисления-восстановления. помогите пожалуйста

Answer 1

Cu + 4HNO3 (КОНЦ) = Cu(NO3)2 + 2NO2 + 2H2O
3Cu + 8HNO3 (РАЗБ) = 3Cu(NO3)2 + 2NO + 4H2O 
Cu - В-ЛЬ
HNO3 - ОК-ЛЬ

Answer 2

Understanding the Oxidation-Reduction Reactions of Dilute and Concentrated Nitric Acid with Copper

When considering the oxidation-reduction reactions of dilute and concentrated nitric acid with copper, it's important to understand the chemical processes involved in these reactions.

Dilute Nitric Acid: Dilute nitric acid behaves as a typical acid, but it also has oxidizing properties. When reacting with metals, it can produce nitrogen oxides. The reaction of dilute nitric acid with copper involves both oxidation and reduction processes.

Concentrated Nitric Acid: Concentrated nitric acid is a strong oxidizing agent and can react violently with reducing agents. It can oxidize non-active metals, such as copper, to form nitrogen oxides.

Equations for the Reactions:

The reactions of dilute and concentrated nitric acid with copper can be represented by the following equations:

Dilute Nitric Acid: The reaction of dilute nitric acid with copper can be represented by the following equation: ``` 3Cu + 8HNO3 → 3Cu(NO3)2 + 2NO + 4H2O [[3]] ``` In this reaction, copper is oxidized from an oxidation state of 0 to +2, and nitrogen in nitric acid is reduced from +5 to +2.

Concentrated Nitric Acid: The reaction of concentrated nitric acid with copper can be represented by the following equation: ``` 3Cu + 8HNO3 → 3Cu(NO3)2 + 2NO2 + 4H2O [[3]] ``` In this reaction, copper is oxidized from an oxidation state of 0 to +2, and nitrogen in nitric acid is reduced from +5 to +4.

Conclusion:

In both cases, the copper is oxidized, and the nitric acid is reduced. The difference lies in the products formed due to the concentration of the nitric acid. Dilute nitric acid produces nitric oxide (NO), while concentrated nitric acid produces nitrogen dioxide (NO2) as a result of the oxidation-reduction reactions with copper.