Correct Net Ionic Equations | Eliminate Spectator Ions | Homework Help

[Qube]

Homework Statement

Which of the following is a correctly written net ionic equation?

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Homework Equations

Net ionic equation eliminate all spectator ions.

The Attempt at a Solution

It looks to me as if four of the answer choices are correct. All but one eliminate the spectator ions. How do I distinguish among the answer choices?

 

[Borek]

It is not only about spectator ions, think harder.

How do you think, is the first equation correct?

 

[Qube]

I think I see it now.

Choice 1) That's not sulfate. Sulfate has a -2 charge.

2) All nitrates are soluble so the left and right hand sides of that equation are the same thing/can be represented with either the subscript, (aq), or as individual ions.

3) Everything here is correct. No incorrect polyatomic ions, and a precipitate actually forms, as most fluorides are insoluble (CaF2, MgF2, etc.)

4) Not a net ionic equation. No ions written, for one thing.

5) All sulfates are soluble except sulfate compounds containing Ca, Ba, Sr, Hg, Ag, or Pb. Zinc sulfate is soluble.

 

[Keipi]

Which one do you then think is wrong?

As a tip, try writing all of the complete ionic equation first and indicate all of the phases. Then look at which of the ions remain in the same phase to write the net ionic equation. You should be able to figure out which ones are wrong and which ones are right at that point.

As an example:

Reaction: Mg (s) + 2 HCl (aq) --> MgCl₂ (aq) + H₂ (g)
Complete ionic equation: Mg (s) + 2 H⁺ (aq) + 2 Cl^- (aq) --> Mg²⁺ (aq) + 2 Cl^- (aq) + H₂ (g)

Cl^- is the only ion that stays in the same phase on both sides of the reaction so we can take that out of the equation, the net ionic equation will then be:

Net ionic equation: Mg (s) + 2 H⁺ (aq) --> Mg²⁺ (aq)+ H₂ (g)

 

[DeeNos]

As a scientist, it is important to understand the concept of spectator ions and how they can be eliminated from net ionic equations. A spectator ion is an ion that appears on both the reactant and product side of a chemical equation and does not participate in the actual chemical reaction. Therefore, it can be eliminated from the net ionic equation to simplify the representation of the reaction.

To distinguish among the answer choices, you can follow these steps:

1. Identify the ions that are present on both the reactant and product side of the equation. These are the spectator ions.

2. Write the net ionic equation by eliminating the spectator ions. This will leave you with only the ions that participate in the reaction.

3. Compare your net ionic equation with the answer choices provided. The correct net ionic equation should only have the ions that are involved in the reaction and should not include any spectator ions.

4. If there are still multiple correct answer choices, you can further confirm the correct net ionic equation by balancing the charges and making sure that the number of each type of ion is the same on both sides of the equation.

In summary, to distinguish among the answer choices, you need to identify and eliminate the spectator ions and ensure that the remaining ions are balanced and represent the actual chemical reaction. I hope this helps with your homework. If you have any further questions, please do not hesitate to ask.