Question

What net lonic equation can be derived from this complete ionic equation? `2Fe^(3+)(aq) + 6Cl^-(aq) + 6Na^+(aq) + 3CO_3^(2-)(aq) -> Fe_2(CO_3)_3(s) + 6Cl^-(aq) + 6Na^+(aq)`?

Answer 1

`2Fe^(3+) + 3CO_3^(2-) rarr Fe_2(CO_3)_3(s)darr`

Explanation:

Simply cancel out the common items, the ones that do not undergo chemical change in the original equation:

`2Fe^(3+) + cancel(6Cl^(-) + 6Na^(+)) + 3CO_3^(2-) rarr Fe_2(CO_3)_3(s)darr +cancel(6Na^(+) + 6Cl^(-))`

Are mass and charge balanced in the given equation? If they are not, you know that the equation cannot be accepted as a representation of reality. In other words these equations must obey stoichiometry.

Answer 2

Cancel the "spectator ions" - that undergo no changes, and the net ionic equation appears. Details follow.

Explanation:

In a net ionic equation you omit any particles (generally ions) that are not changed in any way as the reaction occurs.

In this case, this applies to the `Na^+` and `Cl^-` ions.

So, the net ionic equation is:

`2Fe^(3+) (aq)+ 3 CO_3^(2-)(aq) rarr Fe_2(CO_3)_3(s)`