once again im lost in chemistry....a little help please??

Question

Ok here we go!
When aqueous silver nitrate reacts with aqueous sodium chromate, soluble sodium nitrate forms and silver chromate precipitates out of solution.

a. Write the balanced molecular equation for this reaction.

b. Write the balanced complete ionic equation for this reaction?

c. What are the spectator ions in this reaction?

d. Write the net ionic equation for this reaction.

Answer 1

a. show all compounds in compound form

2 AgNO3(aq) + Na2CrO4(aq) --> 2 NaNO3(aq) + Ag2CrO4(s)

(aq) means aqueous or the substance dissolves in water
(s) means solid or the substance does NOT dissolve in water and is often referred to as a "precipitate"

b. show aqueous compounds as separate ions - keep solid as one solid (don't separate into ions)

2 Ag+1(aq) + 2 NO3-1(aq) + 2 Na+1(aq) + CrO4-2(aq) -->
2 Na+1(aq) + 2 NO3-1(aq) + Ag2CrO4(s)

c. spectator ions are the exact same on BOTH sides of the equation - the Na+1 ions and the NO3-1 ions are the spectator ions in this reaction

d. show only the NON spectator ions

2 Ag+1(aq) + CrO4-2(aq) --> Ag2CrO4(s)

Answer 2

Assuming the silver is at the oxidation state of 2+, this would be the balanced molecular equation:

Ag(NO3)2 + Na2CrO4 -------> 2NaNO3 + AgCrO4

Putting the two in front of the sodium nitrate ensures there is balance of elements on both sides of the equation. Make sure when writing this on paper, though, that you indicate which compounds are aqueous and which are solid. In this case, all are aqueous except for the silver chromate on the right side of the equation.

B. Ag2(+) + 2NO3(-) + 2Na(+) + CrO4(2-) -----> 2Na(+) + 2NO3(-) + AgCrO4

Everything in paratheses indicates the charge of the ion. For this question, everything that is aqueous will dissociate in solution into its ions. So, everything that is listed as aqueous in the problem, you must show each ion with its respective charge and how many moles are present. Make sure to keep the equation balanced.

C. The spectator ions are the ions that do not take part in the reaction stated in the problem. They can be determined by analyzing the balanced ionic equation. Basically, ions that are present on both sides of the equation are the spectator ions. So, in this case, they are the Nitrate ion and the Sodium ion.

D. The net ionic equation is the balanced ionic equation minus the spectator ions. Basically, it is just showing what ions are participating in the reaction, usually some sort of precipitation.

Ag(2+) + CrO4(2-) ------> AgCrO4

Also remember, anytime you are writing balanced equations, it is important to indicate which are solid and which are aqueous.


I hope this is all correct. I havn't taken general chem for years,as I am now in Biochem, but if there is a mistake, please correct.

Answer 3

2AgNO3 + Na2CrO4 --> 2NaNO3 + Ag2CrO4

2Ag(+) + 2NO3(-) + 2Na(+) + CrO4(2-) --> 2NO3(-) + 2Na(+) + Ag2CrO4

Spectators: NO3(-) and Na(+)

Net: 2Ag(+) + CrO4(2-) --> Ag2CrO4