[bidiboom]

Hi guys,

I have a questionmark in my mind about a question:

2Na₃PO₄ (aq) + 3Mg(NO₃)₂ (aq) Mg₃(PO₄)₂ (s) + 6NaNO₃ (aq)
The amounts getting in the reaction are 0.1 mol and 0.1mol.

It is not the answer, but one of the answers related with this question is:
"Since nitrate ion is a spectator ion, the concentration of nitrate ion in the final solution will be the same as in the original magnesium nitrate solution."

This is true to me. The NO₃ ion is a spectator in the aqueous solution and it gets out, 0.1mol, as it gets in, 0.1mol. Because its not actually getting in the reaction.

What do you think? I am distressed for I will take the test Saturday.. I cant see anything anymore.. where am I wrong? If you give me a clue, it will be relieving.. thank you guys..     

[UG]

I am not sure what exactly you are asking? 

[Borek]

The amounts getting in the reaction are 0.1 mol and 0.1mol.

It is not the answer, but one of the answers related with this question is:
"Since nitrate ion is a spectator ion, the concentration of nitrate ion in the final solution will be the same as in the original magnesium nitrate solution."

In general there is not enough information to answer. However, if you are given information about volumes mixed, think what is the final volume.

[bidiboom]

you're right.. Ok then I will pass the question as it is:

..Na₃PO₄ (aq) + ..Mg(NO₃)₂ (aq) ..Mg₃(PO₄)₂ (s) + ..NaNO₃ (aq)

Equal volumes of 0.10M sodium phosphate and 0.10M magnesium nitrate are mixed according to the unbalanced reaction equation above. Which of the following statements is true regarding the reaction?

A) When the reaction is complete, the concentrations of both magnesium and phosphate are essentially 0.

B) Magnesium nitrate is the limiting reactant.

C) Sodium phosphate is the limiting reactant.

D) Since nitrate ion is a spectator ion, the concentration of nitrate ion in the final solution will be the same as in the original magnesium nitrate solution.

E) Na₃PO₄ and Mg(NO₃)₂ react in a 1:1 ratio.

edit: Borek sorry, I was replying UG at the moment you were replying as well, so I couldnt see your post.. but now the question is more clear I think..
 

[AWK]

You completed coefficients for this reaction  in the first post - on this basis now think about points: B) or C) or E)

[bidiboom]

You completed coefficients for this reaction  in the first post - on this basis now think about points: B) or C) or E)

Ok, magnesium nitrate is the limiting reactant.. but the option D, looks true as well.. I try to understand why option D should be false In my first post I told my approach and where of it is wrong I dont know. 

[Borek]

the option D, looks true as well.. I try to understand why option D should be false In my first post I told my approach and where of it is wrong I dont know. 

And in my first post I already gave you an important hint. Amount of nitrate didn't change, but something else has changed.

[bidiboom]

the option D, looks true as well.. I try to understand why option D should be false In my first post I told my approach and where of it is wrong I dont know. 

And in my first post I already gave you an important hint. Amount of nitrate didn't change, but something else has changed.

Thats confusing me: if the amount doesnt change, then the "concentration" as well shouldnt change? I mean the same spectator ion concentration=the same spectator ion amount

This is ironic, because actually I am very good in stoichiometric calculations.. what happened to me now I constantly miss something..   

[sjb]

Thats confusing me: if the amount doesnt change, then the "concentration" as well shouldnt change? I mean the same spectator ion concentration=the same spectator ion amount

This is ironic, because actually I am very good in stoichiometric calculations.. what happened to me now I constantly miss something..   

What's the definition of concentration?

[bidiboom]

sjb, please dont misunderstand me, but normally I am used to study on my own and I am not used to get a direct support from anybody. So in general I am used to get a piece of information and chew it on my own in my mind, and its really hard for me to go on step by step on a specific thinking path with someone. I am getting more confused

Is it possible to tell the answer? Then I can produce my own thinking path on it.

[Borek]

If you didn't get it up to now, you will not get it after knowing the answer. You got more than enough hints, but you have not tried to follow them. You are wasting our time.

[fledarmus]

Let me draw your attention to a few things that might clear this up:

you're right.. Ok then I will pass the question as it is:

..Na₃PO₄ (aq) + ..Mg(NO₃)₂ (aq) ..Mg₃(PO₄)₂ (s) + ..NaNO₃ (aq)

Equal volumes of 0.10M sodium phosphate and 0.10M magnesium nitrate are mixed according to the unbalanced reaction equation above. Which of the following statements is true regarding the reaction?

A) When the reaction is complete, the concentrations of both magnesium and phosphate are essentially 0.

B) Magnesium nitrate is the limiting reactant.

C) Sodium phosphate is the limiting reactant.

D) Since nitrate ion is a spectator ion, the concentration of nitrate ion in the final solution will be the same as in the original magnesium nitrate solution.

E) Na₃PO₄ and Mg(NO₃)₂ react in a 1:1 ratio.

edit: Borek sorry, I was replying UG at the moment you were replying as well, so I couldnt see your post.. but now the question is more clear I think..
 

And now for the questions:

1) What volume of the original magnesium nitrate solution did you use?

2) What was the concentration of magnesium nitrate in that original solution?

3) What was the total volume of material in the reaction mixture?

4) What was the concentration of magnesium nitrate in your reaction mixture?

5) Is the concentration of magnesium nitrate in the original solution (2) equal to the concentration of magnesium nitrate in the reaction mixture (4)?

[bidiboom]

If you didn't get it up to now, you will not get it after knowing the answer. You got more than enough hints, but you have not tried to follow them. You are wasting our time.

No I am not. Every second of the people here, spent for me, will be evaluated for the good of some other people somewhere else. You did not waste your time. But you wanted me to be the person that will satisfy you. I did not do that and you felt dissatisfied with me. I simply dont think in a way I am forced into. I dislike this and also I am not used to get direct guidance of people and you wanted to be my guide, whats more you did it as if you were guiding a moron. That was actually disrespectful.

If you have something to share, do it with respect, or you dont waste the whole day of people who are asking for only one single sentence. You dont have to, but if you consider to give someone something, dont play with it in a way to please yourself, just give and walk away.

OR do not.

[bidiboom]

Let me draw your attention to a few things that might clear this up:

you're right.. Ok then I will pass the question as it is:

..Na₃PO₄ (aq) + ..Mg(NO₃)₂ (aq) ..Mg₃(PO₄)₂ (s) + ..NaNO₃ (aq)

Equal volumes of 0.10M sodium phosphate and 0.10M magnesium nitrate are mixed according to the unbalanced reaction equation above. Which of the following statements is true regarding the reaction?

A) When the reaction is complete, the concentrations of both magnesium and phosphate are essentially 0.

B) Magnesium nitrate is the limiting reactant.

C) Sodium phosphate is the limiting reactant.

D) Since nitrate ion is a spectator ion, the concentration of nitrate ion in the final solution will be the same as in the original magnesium nitrate solution.

E) Na₃PO₄ and Mg(NO₃)₂ react in a 1:1 ratio.

edit: Borek sorry, I was replying UG at the moment you were replying as well, so I couldnt see your post.. but now the question is more clear I think..
 

And now for the questions:

1) What volume of the original magnesium nitrate solution did you use?

2) What was the concentration of magnesium nitrate in that original solution?

3) What was the total volume of material in the reaction mixture?

4) What was the concentration of magnesium nitrate in your reaction mixture?

5) Is the concentration of magnesium nitrate in the original solution (2) equal to the concentration of magnesium nitrate in the reaction mixture (4)?

Fledarmus thank you for your time, but I did not read the post.

There is no need for one another post in this thread, though its up to you, but I am done with it, and with here as well. Thank you for all, centilmen.