Question

What is the a). balanced molecular equation b). total ionic equation c). net ionic equation for copper metal and aluminum nitrate? I tried answering them below, not sure if they're right though

Answer 1

a). 3Cu(s)+2Al(NO3)3(aq)-->3Cu(NO3)2(aq)+2Al(s)
b). 3Cu(s)+2Al^3+(aq)+3NO3^-(aq)-->3Cu^2+(aq)+6NO3^-(aq)+2Al(s)
c). Same as b).; there are no spectator ions

Are my answers correct?

Answer 2

I think the first term of b) should be 6NO3^-(aq)

Answer 3

Oh yeah I didn't multiply the 2. Thanks for pointing that out! But the rest of the equations are correct? @kc_kennylau

Answer 4

nitrate ion is the spectator ion

Answer 5

So I only need to change c). is 3Cu+2Al-->3Cu+2Al right? Okay thank you!

Answer 6

Don't forget the charges :)

Answer 7

& state symbols

Answer 8

Yep

Answer 9

I just wanna ask though, since copper ions can either be 1+ or 2+, in cases like this, how do I know which charge to use??

Answer 10

Well you need to know the compound formed

Answer 11

Wait, no you don't

Answer 12

\(3Cu(s)+2Al^{3+}(aq)\rightarrow3Cu^{2+}(aq)+2Al(s)\) makes sense, but \(3Cu(s)+2Al^{3+}(aq)\rightarrow3Cu^+(aq)+2Al(s)\) doesn't.

Answer 13

Wait this method doesn't work because the numbers are obtained AFTER balancing

Answer 14

So yes you need to know the compound formed

Answer 15

But copper ion is usually copper (II) ion

Answer 16

@elleblythe : May I enquire what grade of Chemistry is this question in?

Answer 17

@shiraz14 College general chemistry

Answer 18

@elleblythe : Please refer to the Electrochemical potential table for reduction potentials of Al^3+/Al and Cu^2+/Cu^+ as well as Cu^2+/Cu and Cu^+/Cu. Compare the individual reduction potentials to decide if Cu will be oxidized to Cu^+/Cu^2+ under these conditions.

Answer 19

How about if it's calcium nitrate and sodium phosphate?
a). 3Ca(NO3)2(aq)+2Na3PO4(aq)-->Ca3(PO4)2(aq)+6NaNO3(aq)
b). 3Ca^2+(aq)+6NO3^-(aq)+6Na^+(aq)+2PO4^3-(aq)-->same as left side
c). all are spectator ions

Answer 20

@kc_kennylau : Please assist to respond. I need to log off now. Goodbye.

Answer 21

Are you sure that they are all aq? I haven't checked any information though

Answer 22

I think so.. it says in the solubility rules that compounds with NO3 are soluble, Na is soluble, but I'm not so sure about the PO4

Answer 23

@elleblythe : Na3PO4 is soluble & yes, your second set of equations is correct.