Balance the following redox reaction in basic solution. H2(g)+Fe3+(aq) ---> H2O(l)+Fe2+(aq)
H2 + 2OH^- ==> 2H2O + 2e
Fe^3+ + e ==> Fe^2+
Multiply eqb 1 bt 1 and eqn 2 by 2, then add.
Alright, let's tackle this redox reaction with a touch of humor! Here's how we can balance it:
First, let's balance the atoms other than hydrogen and oxygen. As we see, the hydrogen atoms are already balanced. Moving on to the oxygens, we have two on the left side and one on the right side. So, let's double the water on the right side and rewrite our equation:
H2(g) + Fe3+(aq) ---> 2H2O(l) + Fe2+(aq)
Now, we're left with balancing the hydrogen atoms and charges. On the left side, we have two hydrogen atoms, while on the right side, we have four. To balance this, we can add two hydroxide ions (OH-) to the left side:
H2(g) + Fe3+(aq) + 2OH-(aq) ---> 2H2O(l) + Fe2+(aq)
Now, let's deal with the charges. On the left side, we have a +3 charge from the iron(III) ion and a -1 charge from each hydroxide ion. On the right side, we have a +2 charge from the iron(II) ion. To balance this, we can add three electrons (e-) to the left side:
H2(g) + Fe3+(aq) + 2OH-(aq) + 3e- ---> 2H2O(l) + Fe2+(aq)
And voila! We have successfully balanced the redox reaction in basic solution.
To balance the redox reaction in basic solution, follow these steps:
Step 1: Split the reaction into two half-reactions.
Half-reaction 1: H2(g) → H2O(l)
Half-reaction 2: Fe3+(aq) → Fe2+(aq)
Step 2: Balance the atoms.
For Half-reaction 1, there are two hydrogen (H) atoms on the left side and two on the right side, so this step is already balanced.
For Half-reaction 2, there is one iron (Fe) atom on both the left and right side, so this step is also balanced.
Step 3: Balance the charges by adding electrons (e-) to the side that needs them.
For Half-reaction 1, there are no charges.
For Half-reaction 2, Fe3+ loses three electrons to become Fe2+. So, add three electrons to the left side.
Half-reaction 1: H2(g) → H2O(l) + 2e-
Half-reaction 2: Fe3+(aq) + 3e- → Fe2+(aq)
Step 4: Balance the electrons in both half-reactions.
Multiply Half-reaction 1 by 3, and Half-reaction 2 by 2 to balance the electrons in both half-reactions.
Half-reaction 1: 3H2(g) → 3H2O(l) + 6e-
Half-reaction 2: 2Fe3+(aq) + 6e- → 2Fe2+(aq)
Step 5: Balance the elements other than H and O.
For hydrogen (H), there are six on the right side in Half-reaction 1. So, add 6 H+ ions to the left side in Half-reaction 2.
Half-reaction 1: 3H2(g) → 3H2O(l) + 6e-
Half-reaction 2: 2Fe3+(aq) + 6e- + 6H+ → 2Fe2+(aq)
Step 6: Balance the oxygen (O) atoms by adding OH- ions.
For oxygen (O), there are six in Half-reaction 1. So, add six OH- ions to the left side in Half-reaction 2.
Half-reaction 1: 3H2(g) → 3H2O(l) + 6e-
Half-reaction 2: 2Fe3+(aq) + 6e- + 6H+ + 6OH- → 2Fe2+(aq)
Step 7: Combine the half-reactions.
Now, combine both half-reactions by canceling out the electrons.
3H2(g) + 2Fe3+(aq) + 6OH- → 3H2O(l) + 2Fe2+(aq) + 6H2O
To balance a redox reaction in basic solution, follow these steps:
Step 1: Split the redox reaction into two half-reactions.
H2(g) -> H2O(l) (oxidation half-reaction)
Fe3+(aq) -> Fe2+(aq) (reduction half-reaction)
Step 2: Balance the atoms and charges in each half-reaction.
Oxidation half-reaction:
H2(g) -> 2H+(aq) + 2e-
Reduction half-reaction:
Fe3+(aq) + e- -> Fe2+(aq)
Step 3: Balance the oxygen atoms by adding water (H2O) to the side that requires oxygen.
Oxidation half-reaction:
H2(g) -> 2H+(aq) + 2e-
Reduction half-reaction:
Fe3+(aq) + e- -> Fe2+(aq) + H2O(l)
Step 4: Balance the hydrogen atoms by adding hydrogen ions (H+) to the side that requires hydrogen.
Oxidation half-reaction:
H2(g) -> 2H+(aq) + 2e-
Reduction half-reaction:
Fe3+(aq) + e- + 2H+ -> Fe2+(aq) + H2O(l)
Step 5: Balance the charges by multiplying one or both of the half-reactions.
Oxidation half-reaction:
2H2(g) -> 4H+(aq) + 4e-
Reduction half-reaction:
3Fe3+(aq) + 3e- + 6H+ -> 3Fe2+(aq) + 3H2O(l)
Step 6: Combine the two half-reactions and simplify if necessary.
2H2(g) + 3Fe3+(aq) + 3H2O(l) -> 4H+(aq) + 2Fe2+(aq) + 3H2O(l)
Step 7: Cancel out any species that appear on both sides of the equation.
2H2(g) + 3Fe3+(aq) -> 4H+(aq) + 2Fe2+(aq) + 3H2O(l)
Therefore, the balanced redox reaction in basic solution is:
2H2(g) + 3Fe3+(aq) -> 4H+(aq) + 2Fe2+(aq) + 3H2O(l)