If 5.7 moles of zinc metal react with 8.9 moles of silver nitrate, how many moles of silver metal can be formed, and how many moles of the excess reactant will be left over when the reaction is complete? Unbalanced equation: Zn + AgNO3 → Zn(NO3)2 + Ag Be sure to show all of your work.

Question

If 5.7 moles of zinc metal react with 8.9 moles of silver nitrate, how many moles of silver metal can be formed, and how many moles of the excess reactant will be left over when the reaction is complete?  Unbalanced equation: Zn + AgNO3 → Zn(NO3)2 + Ag  Be sure to show all of your work.

anonymous · Answer

Whenever they mention "unbalanced" that is a sure sign that you need to fix that before doing anything else.

$$Zn + 2 AgNO _{3} \rightarrow Zn(NO _{3})_{2} + 2 Ag$$

With this done, you should see that there will be excess Zn reactant (5.7 - 4.45 moles = 1/25 moles excess reactant) if the reaction can only handle a 1:2 ratio of $$Zn : AgNO _{3}$$.

Finally, since the $$AgNO _{3}$$ and $$Ag$$ have the same coefficients, they will have an equal number of moles (8.9 moles of Ag will form).