In the redox reaction:
4NH3(g)+3O2(g)-->2N2(g)+6H2O(l)
the number of moles of electrons transferred is...
Each N on the left has an oxidation state of -3 and on the right it is zero.
Each O on the left is zero and on the right each O is -2.
To determine the number of moles of electrons transferred in a redox reaction, we need to examine the changes in oxidation states of the elements involved.
In this reaction, nitrogen (N) has an oxidation state of -3 in NH3 and 0 in N2. Oxygen (O) has an oxidation state of 0 in O2 and -2 in H2O.
To balance the change in oxidation states, we can assign a change of 6 units to each nitrogen atom (from -3 to 0), and a change of 8 units to each oxygen atom (from 0 to -2).
Since there are 4 moles of NH3 reacting, we have a total of 4 × 6 = 24 units of oxidation state change for nitrogen.
Similarly, for oxygen, we have 3 × 8 = 24 units of oxidation state change.
Since 1 mole of electrons corresponds to 1 unit of oxidation state change, the total number of moles of electrons transferred is equal to the total units of oxidation state change:
24 units of oxidation state change = 24 moles of electrons transferred.
Therefore, in this reaction, the number of moles of electrons transferred is 24.
To determine the number of moles of electrons transferred in a redox reaction, you need to look at the change in oxidation states of the elements involved.
In this reaction, we can identify two elements whose oxidation states change: nitrogen (N) and hydrogen (H).
Let's start with nitrogen (N):
- In ammonia (NH3), nitrogen has an oxidation state of -3.
- In nitrogen gas (N2), nitrogen has an oxidation state of 0.
Hence, the oxidation state of nitrogen changes from -3 to 0, indicating that it gained 3 electrons per nitrogen atom.
Now let's consider hydrogen (H):
- In ammonia (NH3), hydrogen has an oxidation state of +1.
- In water (H2O), hydrogen has an oxidation state of +1.
Thus, the oxidation state of hydrogen remains the same in this reaction, indicating that no electrons are gained or lost by the hydrogen atoms.
Since each nitrogen atom gains 3 electrons, and there are 2 moles of nitrogen atoms involved in the reaction, the total number of moles of electrons transferred can be calculated as follows:
Number of moles of electrons transferred = (number of moles of nitrogen) × (number of electrons gained per nitrogen atom)
= 2 moles × 3 electrons/mole
= 6 moles of electrons.
Therefore, in the given redox reaction, a total of 6 moles of electrons are transferred.