Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: brocasbrain00 on October 02, 2007, 09:32:20 PM
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1.)
How do I write the chemical formula for the reaction between copper and AgNO3 in solution? I have no idea how to do it, and my teacher never explained it.
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I tried Cu + AgNO3 -----> AgCu + NO3
Is that all?
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2.)
Is the reaction
H2SO4 (aq) + 2CH3NH2 (aq) ----> (CH3NH3)2 SO4 (aq)
a precipitation reaction, an acid-base reaction, or an oxidation-reduction reaction? Explain.
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What do I do?
How can I tell which type of reaction it is?
H2SO4 is an acid, and I guess the H2 is left over after the reaction, or something, but if it is acid-base then how is 2CH3NH2 a base? There is no hydroxide..
I'm so confused.
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I tried Cu + AgNO3 -----> AgCu + NO3
Cu and Ag are both cations, so Cu will not bond to Ag. Try again.
Is the reaction
H2SO4 (aq) + 2CH3NH2 (aq) ----> (CH3NH3)2 SO4 (aq)
a precipitation reaction, an acid-base reaction, or an oxidation-reduction reaction? Explain.
Obviously it isn't a ppt. reaction, since (CH3NH3)2 SO4 is aq. I would say it is an acid/base reaction.
H2SO4 is an acid, and I guess the H2 is left over after the reaction, or something, but if it is acid-base then how is 2CH3NH2 a base? There is no hydroxide..
I'm so confused.
You are using the arrhenius defintion of a base. CH3NH2 is a bronsted-lowry base.
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Cu + AgNO3 -> CuNO3 + Ag
is that right? why is that redox, and how do I know the charge of the Cu with NO3?
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bronsted-lowry, does that say that a base is a proton acceptor, or something like that? If it is, then how do you know that CH3NH2 is a proton-acceptor?
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Cu + AgNO3 -> CuNO3 + Ag
is that right?
yes, but Cu is usually 2+, so CuNO3 becomes Cu(NO3)2. Then you would have to balance the eqn.
why is that redox, and how do I know the charge of the Cu with NO3?
Who said that was redox? If your reactants are aq. then they are already present as ions.
bronsted-lowry, does that say that a base is a proton acceptor, or something like that? If it is, then how do you know that CH3NH2 is a proton-acceptor?
yes. You know CH3NH2 is a proton-acceptor from the eqn. You could probably guess it anyway, since N has a lone pair.
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Who said that was redox? If your reactants are aq. then they are already present as ions.
All single replacement reaction are also redox reactions (though very simple ones)
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How do I write the chemical formula for the reaction between copper and AgNO3 in solution?
What you have is (most likely) METALLIC copper (Cu0) and Ag+ - otherwise question doesn't make sense. Copper gets oxidized and dissolved, silver gets reduced to metal - that's where redox come into play.
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You know CH3NH2 is a proton-acceptor from the eqn.
You don't know reaction equation beforehand, you can write it once you know what is happening in the solution. So this part of your answer is wrong.
You could probably guess it anyway, since N has a lone pair.
And that's much better approach - nitrogen in ammonia has a lone pair and is a Bronsted-Lowry base, same happens with all ammonia derivatives (in which H atoms are replaced by something else).
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You know CH3NH2 is a proton-acceptor from the eqn.
You don't know reaction equation beforehand, you can write it once you know what is happening in the solution. So this part of your answer is wrong.
The equation is given in the initial post.
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The equation is given in the initial post.
Yep, my mistake.