Complete and balance these half-equations. Express as net ionic eqn.

1.) Cr2O7(2−) → Cr(3+) (acidic solution)
So far, I have: Cr2O7(2−) + 14H + 6e(-) →2Cr(3+) + 7H20

2.) C2O4(2−) → CO2 (acidic solution)
Not sure how to do this one.

Thank you.

To balance the half-reaction for the conversion of C2O4(2-) to CO2 in acidic solution, you need to follow these steps:

Step 1: Write the unbalanced half-reaction equation for the oxidation or reduction process.

In this case, we have the oxidation process: C2O4(2-) → CO2.

Step 2: Balance the atoms that change oxidation state.

In this case, the carbon (C) atoms undergo a change in oxidation state. We have two C atoms on the left side and one C atom on the right side. To balance this, we need to add a coefficient of 2 in front of CO2.

C2O4(2-) → 2CO2

Step 3: Balance the oxygens (O) by adding water (H2O).

On the left side, we have 4 oxygen atoms from C2O4(2-). On the right side, we have 4 oxygen atoms from 2CO2. Therefore, the oxygens are already balanced.

C2O4(2-) → 2CO2

Step 4: Balance the hydrogens (H) by adding H+ ions.

On the left side, we have no hydrogen atoms. On the right side, we have 4 hydrogen atoms from 2CO2. Therefore, we need to add 4H+ ions on the left side of the equation.

C2O4(2-) + 4H+ → 2CO2

Step 5: Balance the charges by adding electrons (e-).

On the left side, we have a charge of -2 from the C2O4(2-) ion. On the right side, we have a charge of 0 from the CO2 molecule. To balance the charges, we need to add two electrons (2e-) on the left side.

C2O4(2-) + 4H+ + 2e- → 2CO2

The balanced half-equation for the conversion of C2O4(2-) to CO2 in acidic solution is:

C2O4(2-) + 4H+ + 2e- → 2CO2

To write the overall net ionic equation, you would combine this balanced half-equation with the balanced half-equation from the reduction process occurring in the same reaction. However, since you only provided one half-equation, it is not possible to write the net ionic equation for the complete reaction.

To complete and balance the half-equation for C2O4(2−) → CO2 in an acidic solution, you can follow these steps:

Step 1: Write down the unbalanced equation:

C2O4(2−) → CO2

Step 2: Determine the change in oxidation state:

The oxidation state of carbon in C2O4(2−) is +3, and in CO2, it is +4. Therefore, the change in oxidation state is 4 - 3 = +1.

Step 3: Balance the number of atoms on each side of the equation:

Since there is only one carbon atom on each side of the equation, the carbon atoms are already balanced.

Step 4: Balance the oxygen atoms:

On the left side, there are four oxygen atoms, and on the right side, there are two oxygen atoms. To balance the oxygen atoms, add two water molecules (H2O) to the right side:

C2O4(2−) → CO2 + 2H2O

Step 5: Balance the hydrogen atoms:

On the left side, there are no hydrogen atoms, and on the right side, there are four hydrogen atoms from the water molecules. To balance the hydrogen atoms, add four hydrogen ions (H+) to the left side:

C2O4(2−) + 4H+ → CO2 + 2H2O

Step 6: Balance the charges:

On the left side, the overall charge is -2 from the C2O4(2−) ion. On the right side, the carbon dioxide (CO2) molecule is neutral, and the water (H2O) molecules do not carry charges. To balance the charges, add eight electrons (e-) to the left side:

C2O4(2−) + 4H+ + 8e- → CO2 + 2H2O

Now, the half-equation is balanced. If you want to write the net ionic equation, you need to pair this half-equation with another half-equation for the reduction reaction.