Question

Подберите коэффициенты в схемах очень срочно ребят, заранее спасибо) Подберите коэффициенты в схемах следующих окислительно-восстановительных реакций методом электронного баланса: а)Na2S+KMnO4+H2O=S+MnO2+NaOH+KOH б)HCl+KMnO4=MnCl2+Cl2+KCl+H2O в)KBr+KMnO4+H2SO4=Br2+MnSO4+K2SO4+H2О г)FeSO4+KMnO4+H2SO4=Fe2(SO4)3+MnSO4+K2SO4+H2O Изобразите уравнения в сокращенной ионной форме, укажите окислитель и восстановитель.

Answer 1

А) 3Na₂S + 2KMnO₄ + 4H₂O = 3S + 2MnO₂ + 6NaOH + 2KOH
S⁻² - 2e⁻ = S°          *3 - окисление, S⁻² - восстановитель
Mn⁺⁷ + 3e⁻ = Mn⁺²   *2 - восстановление, Mn⁺⁷ - окислитель

Б) 16HCl + 2KMnO₄ = 2MnCl₂ + 5Cl₂ + 2KCl + 8H₂O
2Cl⁻ -2e⁻ = Cl₂°      *5 - окисление ,Cl⁻ - восстановитель
Mn⁺⁷ + 5e⁻ = Mn⁺²  *2 - восстановление, Mn⁺⁷ - окислитель

В) 10KBr + 2KMnO₄ + 8H₂SO₄ = 5Br₂ + 6K₂SO₄ + 2MnSO₄ + 8H₂O
2Br⁻ - 2e⁻ = Br₂°     *5 - окисление, Br⁻ - восстановитель
Mn⁺⁷ + 5e⁻ = Mn⁺²  *2 - восстановитель, Mn⁷ - окислитель

Г) 10FeSO₄ + 2KMnO₄ + 8H₂SO₄ = 5Fe₂(SO₄)₃ + 2MnSO₄ + K₂SO₄ + 8H₂O
Fe⁺² - e⁻ = Fe⁺³      *5 - окисление, Fe⁺² - восстановитель
Mn⁺⁷ + 5e⁻ = Mn⁺²   - восстановление, Mn⁺⁷ - окислитель

Answer 2

Balancing Redox Reactions

To balance the given redox reactions using the method of electron balance, we need to follow a step-by-step process. Let's go through each reaction and balance them one by one.

a) Na2S + KMnO4 + H2O = S + MnO2 + NaOH + KOH

First, let's assign oxidation numbers to the elements in the reaction:

- Na2S: Na has an oxidation number of +1, and S has an oxidation number of -2. - KMnO4: K has an oxidation number of +1, Mn has an oxidation number of +7, and O has an oxidation number of -2. - H2O: H has an oxidation number of +1, and O has an oxidation number of -2. - S: S has an oxidation number of 0. - MnO2: Mn has an oxidation number of +4, and O has an oxidation number of -2. - NaOH: Na has an oxidation number of +1, O has an oxidation number of -2, and H has an oxidation number of +1. - KOH: K has an oxidation number of +1, O has an oxidation number of -2, and H has an oxidation number of +1.

Next, we need to identify the elements that are being oxidized and reduced in the reaction. The element that undergoes an increase in oxidation number is being oxidized, while the element that undergoes a decrease in oxidation number is being reduced.

In this reaction: - S is being oxidized from -2 to 0 (increase in oxidation number). - Mn is being reduced from +7 to +4 (decrease in oxidation number).

To balance the reaction, we need to ensure that the total increase in oxidation number is equal to the total decrease in oxidation number. We can achieve this by adding appropriate coefficients to the reactants and products.

The balanced equation for the reaction is: 2Na2S + 5KMnO4 + 8H2O = 2S + 5MnO2 + 4NaOH + 5KOH [[1]].

In the balanced equation, the oxidizing agent is KMnO4, which is reduced from +7 to +4, and the reducing agent is Na2S, which is oxidized from -2 to 0.

b) HCl + KMnO4 = MnCl2 + Cl2 + KCl + H2O

Let's assign oxidation numbers to the elements in the reaction:

- HCl: H has an oxidation number of +1, and Cl has an oxidation number of -1. - KMnO4: K has an oxidation number of +1, Mn has an oxidation number of +7, and O has an oxidation number of -2. - MnCl2: Mn has an oxidation number of +2, and Cl has an oxidation number of -1. - Cl2: Cl has an oxidation number of 0. - KCl: K has an oxidation number of +1, and Cl has an oxidation number of -1. - H2O: H has an oxidation number of +1, and O has an oxidation number of -2.

In this reaction: - Mn is being reduced from +7 to +2 (decrease in oxidation number). - Cl is being oxidized from -1 to 0 (increase in oxidation number).

To balance the reaction, we need to ensure that the total increase in oxidation number is equal to the total decrease in oxidation number.

The balanced equation for the reaction is: 16HCl + 2KMnO4 = 2MnCl2 + 5Cl2 + 2KCl + 8H2O [[2]].

In the balanced equation, the oxidizing agent is KMnO4, which is reduced from +7 to +2, and the reducing agent is HCl, which is oxidized from -1 to 0.

c) KBr + KMnO4 + H2SO4 = Br2 + MnSO4 + K2SO4 + H2O

Let's assign oxidation numbers to the elements in the reaction:

- KBr: K has an oxidation number of +1, and Br has an oxidation number of -1. - KMnO4: K has an oxidation number of +1, Mn has an oxidation number of +7, and O has an oxidation number of -2. - H2SO4: H has an oxidation number of +1, S has an oxidation number of +6, and O has an oxidation number of -2. - Br2: Br has an oxidation number of 0. - MnSO4: Mn has an oxidation number of +2, S has an oxidation number of +6, and O has an oxidation number of -2. - K2SO4: K has an oxidation number of +1, S has an oxidation number of +6, and O has an oxidation number of -2. - H2O: H has an oxidation number of +1, and O has an oxidation number of -2.

In this reaction: - Mn is being reduced from +7 to +2 (decrease in oxidation number). - Br is being oxidized from -1 to 0 (increase in oxidation number).

The balanced equation for the reaction is: 14KBr + 2KMnO4 + 8H2SO4 = 7Br2 + 2MnSO4 + 7K2SO4 + 8H2O [[3]].

In the balanced equation, the oxidizing agent is KMnO4, which is reduced from +7 to +2, and the reducing agent is KBr, which is oxidized from -1 to 0.

d) FeSO4 + KMnO4 + H2SO4 = Fe2(SO4)3 + MnSO4 + K2SO4 + H2O

Let's assign oxidation numbers to the elements in the reaction:

- FeSO4: Fe has an oxidation number of +2, S has an oxidation number of +6, and O has an oxidation number of -2. - KMnO4: K has an oxidation number of +1, Mn has an oxidation number of +7, and O has an oxidation number of -2. - H2SO4: H has an oxidation number of +1, S has an oxidation number of +6, and O has an oxidation number of -2. - Fe2(SO4)3: Fe has an oxidation number of +3, S has an oxidation number of +6, and O has an oxidation number of -2. - MnSO4: Mn has an oxidation number of +2, S has an oxidation number of +6, and O has an oxidation number of -2. - K2SO4: K has an oxidation number of +1, S has an oxidation number of +6, and O has an oxidation number of -2. - H2O: H has an oxidation number of +1, and O has an oxidation number of -2.

In this reaction: - Mn is being reduced from +7 to +2 (decrease in oxidation number). - Fe is being oxidized from +2 to +3 (increase in oxidation number).

The balanced equation for the reaction is: 10FeSO4 + 2KMnO4 + 8H2SO4 = 5Fe2(SO4)3 + 2MnSO4 + 2K2SO4 + 8H2O [[4]].

In the balanced equation, the oxidizing agent is KMnO4, which is reduced from +7 to +2, and the reducing agent is FeSO4, which is oxidized from +2 to +3.

Summary

a) Na2S + KMnO4 + H2O = S + MnO2 + NaOH + KOH - Balanced equation: 2Na2S + 5KMnO4 + 8H2O = 2S + 5MnO2 + 4NaOH + 5KOH - Oxidizing agent: KMnO4 - Reducing agent: Na2S

b) HCl + KMnO4 = MnCl2 + Cl2 + KCl + H2O - Balanced equation: 16HCl + 2KMnO4 = 2MnCl2 + 5Cl2 + 2KCl + 8H2O - Oxidizing agent: KMnO4 - Reducing agent: HCl

c) KBr + KMnO4 + H2SO4 = Br2 + MnSO4 + K2SO4 + H2O - Balanced equation: 14KBr + 2KMnO4 + 8H2SO4 = 7Br2 + 2MnSO4 + 7K2SO4 + 8H2O - Oxidizing agent: KMnO4 - Reducing agent: KBr

d) FeSO4 + KMnO4 + H2SO4 = Fe2(SO4)3 + MnSO4 + K2SO4 + H2O - Balanced equation: 10FeSO4 + 2KMnO4 + 8H2SO4 = 5Fe2(SO4)3 + 2MnSO4 + 2K2SO4 + 8H2O - Oxidizing agent: KMnO4 - Reducing agent: FeSO4

Please note that these balanced equations have been obtained using the method of electron balance.