ATAR Notes: Forum
VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: Kopite on November 13, 2007, 07:16:06 pm
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a question asks to draw
Cu(NH3)4(H20)2S04
the answer displays the NH3 and H20 molecules, but not the S04. Y?????
thanks
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a question asks to draw
Cu(NH3)4(H20)2S04
the answer displays the NH3 and H20 molecules, but not the S04. Y?????
thanks
I think I remember that one. Did it ask you to draw the complex ion, or the whole thing? Because the complex ion doesn't include the SO4
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I think I've seen this question before as well. Let me search my exams ...
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a question asks to draw
Cu(NH3)4(H20)2S04
the answer displays the NH3 and H20 molecules, but not the S04. Y?????
thanks
I think I remember that one. Did it ask you to draw the complex ion, or the whole thing? Because the complex ion doesn't include the SO4
yeah just the complex ion, so what would the overall molecule look like with the so4??
also got another question
write the balanced full equation for
solid sodium oxide reacting with dilute sulfuric acid
the sodium goes from NA20====> NaS04
y doesn't the oxidation state change?? i thought NA2 was supposed to act as a base, and accept protons???
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yeah just the complex ion, so what would the overall molecule look like with the so4??
also got another question
write the balanced full equation for
solid sodium oxide reacting with dilute sulfuric acid
the sodium goes from NA20====> NaS04
y doesn't the oxidation state change?? i thought NA2 was supposed to act as a base, and accept protons???
Don't know. They won't ask you to draw a complex ion as well as the other ion together. Well I hope not anyway otherwise I'm screwed :P
Sodium oxide is a basic oxide. Thus when it reacts with an acid, it forms a salt and water.
Na2O + H2SO4 ---> Na2SO4 + H2O
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yeah just the complex ion, so what would the overall molecule look like with the so4??
also got another question
write the balanced full equation for
solid sodium oxide reacting with dilute sulfuric acid
the sodium goes from NA20====> NaS04
y doesn't the oxidation state change?? i thought NA2 was supposed to act as a base, and accept protons???
Don't know. They won't ask you to draw a complex ion as well as the other ion together. Well I hope not anyway otherwise I'm screwed :P
Sodium oxide is a basic oxide. Thus when it reacts with an acid, it forms a salt and water.
Na2O + H2SO4 ---> Na2SO4 + H2O
ok thanks....yeah i probably should have remembered that from unit 3 eh??? are there any others of those general equation writing rule things i should have remembered???
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ok thanks....yeah i probably should have remembered that from unit 3 eh??? are there any others of those general equation writing rule things i should have remembered???
Umm .... you mean like:
acid + base => water + salt
acid + metal carbonate => salt + water + carbon dioxide? (btw you probably won't need this one)
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Hmm I'm not sure but I did a similar sort of question. But it had something to do with ligands having a lone electron pair or something, I'm not sure. Maybe one of the Chem mods can enlighten us. Complex ions are one of my weakest areas.
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ok thanks....yeah i probably should have remembered that from unit 3 eh??? are there any others of those general equation writing rule things i should have remembered???
Umm .... you mean like:
acid + base => water + salt
acid + metal carbonate => salt + water + carbon dioxide? (btw you probably won't need this one)
yeah those are the ones...do i need to know anymore???
and one more question lol
will AgNO3 and SnCl2 react to an appreciable extent??? a NEAP exam says so.....
thanks lol
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yeah those are the ones...do i need to know anymore???
and one more question lol
will AgNO3 and SnCl2 react to an appreciable extent??? a NEAP exam says so.....
thanks lol
lol ... I guess just know acid + base, acid + water, base + water
I'm assuming AgNO3 and SnCl2 are aqueous? According to the electrochemical series:
Cl2 ---> 2Cl-
O2 + 4H+ + 4e- ---> 2H2O
Ag+ ---> Ag
Sn2+ ---> Sn
I don't see a spontaneous reaction there .... better ask coblin this one :P
As for the ligands thing - according to my textbook:
"Complex ions may be formed with ligands other than water. Polar molecules, such as ammonia, which contain an non-bonding pair of electrons, are particularly effective as ligands."
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Yay, now I can reply without stealing Nina's turn to post/helping streak etc
There is on the electrochemical series somewhere Sn4+ + 2e- -> Sn2+. That's what the question would have been using. But it's not on VCAA's one, so don't worry about it :)
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yeah those are the ones...do i need to know anymore???
and one more question lol
will AgNO3 and SnCl2 react to an appreciable extent??? a NEAP exam says so.....
thanks lol
lol ... I guess just know acid + base, acid + water, base + water
I'm assuming AgNO3 and SnCl2 are aqueous? According to the electrochemical series:
Cl2 ---> 2Cl-
O2 + 4H+ + 4e- ---> 2H2O
Ag+ ---> Ag
Sn2+ ---> Sn
I don't see a spontaneous reaction there .... better ask coblin this one :P
As for the ligands thing - according to my textbook:
"Complex ions may be formed with ligands other than water. Polar molecules, such as ammonia, which contain an non-bonding pair of electrons, are particularly effective as ligands."
yeah thanks...i think we might've interpreted the question wrong, it asks for a reaction, but does not necessarily state it had to be with those elemental ions. so yeah it should be right. water will react instead of chlorine, so there will be a reaction lol
thanks for that ligand info
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Well, I'm not sure what VCE does, because they do their ligands completely wrong! The formula should be:
[Cu(NH3)4(H2O)2]SO4
The SO4 2- ion is just a "counterion" to balance the charge of the overall complex in the square brackets. Copper is in an octahedral 6 coordinate complex, with the ligands NH3 and H2O.
NH3 and H2O are the only ones you show the dotted lines linking to, because they are the actual ligands. The SO4 2- "counterion" only balances out the +2 charge that the copper centre possesses, but it is only an electrostatic attraction (as opposed to a ligand interaction, i.e.: the dotted lines you use in VCE).
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Well, I'm not sure what VCE does, because they do their ligands completely wrong! The formula should be:
[Cu(NH3)4(H2O)2]SO4
The SO4 2- ion is just a "counterion" to balance the charge of the overall complex in the square brackets. Copper is in an octahedral 6 coordinate complex, with the ligands NH3 and H2O.
NH3 and H2O are the only ones you show the dotted lines linking to, because they are the actual ligands. The SO4 2- "counterion" only balances out the +2 charge that the copper centre possesses, but it is only an electrostatic attraction (as opposed to a ligand interaction, i.e.: the dotted lines you use in VCE).
ic. umm...i probably just wrote it out wrong, i was in a bit of a rush, sorry. we don't really have to know about the counterion right???
thanks for the help.
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oh and coblin, do you have any advice on the writing of equations??? there seems to be at least 2 options for every reaction!!!! are the general equations we learnt in unit 3 sufficient for unit 4???
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oh and coblin, do you have any advice on the writing of equations??? there seems to be at least 2 options for every reaction!!!! are the general equations we learnt in unit 3 sufficient for unit 4???
Yeah, I don't know what you mean by the general equations though... that was more of a year 10 or year 11 thing. I think if you mean those acid + base reactions... then you might want to have a look at some in your text book: they're not particularly as easy because if you have an acidic oxide with no free H+ (i.e.: SO2), what do you do? :P
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Well, I'm not sure what VCE does, because they do their ligands completely wrong! The formula should be:
[Cu(NH3)4(H2O)2]SO4
The SO4 2- ion is just a "counterion" to balance the charge of the overall complex in the square brackets. Copper is in an octahedral 6 coordinate complex, with the ligands NH3 and H2O.
NH3 and H2O are the only ones you show the dotted lines linking to, because they are the actual ligands. The SO4 2- "counterion" only balances out the +2 charge that the copper centre possesses, but it is only an electrostatic attraction (as opposed to a ligand interaction, i.e.: the dotted lines you use in VCE).
We don't have to draw in the counterion when it asks to draw the complex, right?
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Well, I'm not sure what VCE does, because they do their ligands completely wrong! The formula should be:
[Cu(NH3)4(H2O)2]SO4
The SO4 2- ion is just a "counterion" to balance the charge of the overall complex in the square brackets. Copper is in an octahedral 6 coordinate complex, with the ligands NH3 and H2O.
NH3 and H2O are the only ones you show the dotted lines linking to, because they are the actual ligands. The SO4 2- "counterion" only balances out the +2 charge that the copper centre possesses, but it is only an electrostatic attraction (as opposed to a ligand interaction, i.e.: the dotted lines you use in VCE).
We don't have to draw in the counterion when it asks to draw the complex, right?
Nope. If you want to be safe, you can just draw the complex, put it in square brackets, with the charge outside, then draw the SO4 2- ion next to it (and there wouldn't be any dashed lines indicating an interaction... it's just how you write ionic structures, you write the cation then the anion).