Fe3+ + I1- �¨ Fe2+ + I2
1. Balance the equation
2. Which element is being oxidized?
3. Which element is the reducing agent?
two I- ions lost an electron to form I2
so therefore, Fe+- must gain two electrons, so it takes two of them
2Fe+++ + 2I- >>> 2Fe++ + I2
1. To balance the equation, we need to make sure that the number of each type of atom is the same on both sides.
Fe3+ + I1- ⟶ Fe2+ + I2
To balance the charge, we need to add one electron to the left side:
Fe3+ + I1- + 1e- ⟶ Fe2+ + I2
Now the equation is balanced.
2. In this equation, iron (Fe) is being oxidized. This is because the iron is going from a +3 oxidation state (Fe3+) to a +2 oxidation state (Fe2+). Oxidation involves the loss of electrons, so since iron is losing electrons, it is being oxidized.
3. The reducing agent is the substance that causes another substance to be reduced (or gain electrons). In this equation, iodide ion (I1-) is the reducing agent. This is because it is causing the iron (Fe) to be reduced, as iron gains electrons when it goes from Fe3+ to Fe2+.
To balance the equation Fe3+ + I- → Fe2+ + I2, follow these steps:
1. Count the number of each type of atom on both sides of the equation.
Fe: 1 Fe on the left, 1 Fe on the right
I: 1 I on the left, 2 I on the right
The equation is not balanced as the number of I atoms is different on each side.
2. Balance the elements one at a time, starting with the ones that appear in the fewest compounds.
Begin with I. Place a coefficient of 2 in front of I- on the left side to balance the number of I atoms: 2I-.
Fe3+ + 2I- → Fe2+ + I2
3. Now, check the other elements: Fe.
There is 1 Fe atom on both sides, so Fe is already balanced.
The balanced equation is:
Fe3+ + 2I- → Fe2+ + I2
Next, let's determine which element is being oxidized and which element is the reducing agent:
• Oxidation is the loss of electrons, and the substance that undergoes oxidation is called the reducing agent.
• Reduction is the gain of electrons, and the substance that undergoes reduction is called the oxidizing agent.
In the given equation, Fe3+ (iron in the +3 oxidation state) is being reduced to Fe2+ (iron in the +2 oxidation state). Therefore, Fe3+ is being reduced, and it is the substance undergoing reduction and is the oxidizing agent.
On the other hand, I- (iodine in the -1 oxidation state) is being oxidized to I2 (iodine in the 0 oxidation state). Therefore, I- is being oxidized, and it is the substance undergoing oxidation and is the reducing agent.
Summary:
1. The balanced equation is Fe3+ + 2I- → Fe2+ + I2.
2. Fe3+ is being reduced and is the oxidizing agent.
3. I- is being oxidized and is the reducing agent.