Question

Помогите, химия!!! Методом полуреакций подберите коэффициенты в схеме окислительно - восстановительной реакции AgNO3 + PH3 + H2O → Ag + H3PO4 + HNO3 . Определите окислитель и восстановитель , тип ОВР , молярную массу эквивалента окислителя и восстановителя .

Answer 1

8AgNO3+PH3+4H2O=8Ag+H3PO4+8HNO3

P -3    -8e =   P+5 восст

Ag +    +1  = Ag 0   окисл

Answer 2

Balancing the Redox Reaction:

To balance the redox reaction using the half-reaction method, we need to separate the reaction into two half-reactions: the oxidation half-reaction and the reduction half-reaction.

The given reaction is: AgNO3 + PH3 + H2O → Ag + H3PO4 + HNO3

Let's start by identifying the oxidation and reduction half-reactions.

Oxidation Half-Reaction:

In the given reaction, the element Ag (silver) is reduced from Ag+ to Ag. Therefore, the oxidation half-reaction involves the loss of electrons by Ag+.

Ag+ → Ag

Reduction Half-Reaction:

In the given reaction, the element P (phosphorus) is oxidized from -3 to +5. Therefore, the reduction half-reaction involves the gain of electrons by P.

PH3 → H3PO4

Now, let's balance the half-reactions.

Balancing the Oxidation Half-Reaction:

To balance the oxidation half-reaction, we need to balance the number of atoms on both sides of the equation and the charge.

Ag+ → Ag

The number of Ag atoms is already balanced, and the charge is also balanced. Therefore, the oxidation half-reaction is already balanced.

Balancing the Reduction Half-Reaction:

To balance the reduction half-reaction, we need to balance the number of atoms on both sides of the equation and the charge.

PH3 → H3PO4

The number of P atoms is already balanced, but the number of H and O atoms is not balanced. To balance the H atoms, we need to add 3 H2O molecules to the right side of the equation.

PH3 + 3H2O → H3PO4

Now, the number of H atoms is balanced, but the number of O atoms is not balanced. To balance the O atoms, we need to add 3 O2 molecules to the left side of the equation.

PH3 + 3H2O + 3O2 → H3PO4

Now, the number of P, H, and O atoms is balanced, but the charge is not balanced. To balance the charge, we need to add 6 electrons (e-) to the left side of the equation.

PH3 + 3H2O + 3O2 + 6e- → H3PO4

Now, the reduction half-reaction is balanced.

Combining the Half-Reactions:

To combine the half-reactions, we need to multiply each half-reaction by a coefficient so that the number of electrons gained in the reduction half-reaction is equal to the number of electrons lost in the oxidation half-reaction.

Multiplying the oxidation half-reaction by 6 and the reduction half-reaction by 2, we get:

6Ag+ → 6Ag (oxidation half-reaction) 2PH3 + 6H2O + 6O2 + 12e- → 2H3PO4 (reduction half-reaction)

Now, let's add the two half-reactions together:

6Ag+ + 2PH3 + 6H2O + 6O2 + 12e- → 6Ag + 2H3PO4

Simplifying the equation, we get:

6Ag+ + 2PH3 + 6H2O + 6O2 → 6Ag + 2H3PO4

Identifying the Oxidizing and Reducing Agents:

In the balanced redox reaction, the oxidizing agent is the species that gets reduced, while the reducing agent is the species that gets oxidized.

In this reaction, Ag+ gets reduced to Ag, so Ag+ is the oxidizing agent. PH3 gets oxidized to H3PO4, so PH3 is the reducing agent.

Determining the Type of Redox Reaction:

The type of redox reaction can be determined by examining the changes in oxidation states of the elements involved.

In this reaction, the oxidation state of Ag changes from +1 to 0, indicating a reduction. The oxidation state of P changes from -3 to +5, indicating an oxidation. Therefore, this is a combination of a reduction and an oxidation reaction, also known as a redox reaction.

Calculating the Molar Mass of the Oxidizing and Reducing Agents:

To calculate the molar mass of the oxidizing and reducing agents, we need to know the molar masses of AgNO3 and PH3.

The molar mass of AgNO3 (silver nitrate) is calculated as follows: AgNO3 = (1 * Ag) + (1 * N) + (3 * O) = 107.87 g/mol + 14.01 g/mol + (3 * 16.00 g/mol) = 169.87 g/mol

The molar mass of PH3 (phosphine) is calculated as follows: PH3 = (1 * P) + (3 * H) = 30.97 g/mol + (3 * 1.01 g/mol) = 33.97 g/mol

Therefore, the molar mass of the oxidizing agent (AgNO3) is 169.87 g/mol, and the molar mass of the reducing agent (PH3) is 33.97 g/mol.

Note: The molar mass of the oxidizing and reducing agents is calculated based on the given chemical formulas and the atomic masses of the elements involved.

I hope this helps! Let me know if you have any further questions.