Chemistry
posted by Alex on .
Electron Transfer Theory
Write an label the oxidation and reduction halfreaction equations.
a) Ni(s) + Cu(NO3)2(aq) > Cu(s)+ Ni(No3)2(aq)
oxidation  Ni(s) > Ni2+(aq) + 2e
reduction  Cu2+(aq) + 2e > Cu(s)
b) Pb(s) + Cu(NO3)2(aq) > Cu(s) + Pb(NO3)2(aq)
oxidation  Pb(s) > Pb2+(aq) + 2e
reduction  Cu2+(aq) +2e > Cu(s)
c) Ca(s) + 2HNO3(aq) > H2(g) + Ca(NO3)2(aq)
oxidation  Ca(s) > Ca2+(aq) + 2e
reduction  2H+(aq) + 2e > H2(g)
d) 2Al(g)+ Fe2O3(s) > 2Fe(l) + Al2O3(s)
oxidation  2Al >
I have no idea what to do with the last one. If I made any mistakes or did anything wrong can someone correct them.
Oxidation Numbers
Assign oxidation numbers to chloride in each of the follow chemicals.
HCl = +1?
Cl2 = 0?
NaClO = ?
Cl = 1?
HClO3 = either +1 or 3?
ClO3 = 3?
KClO2  +2?
ClO2 = +2?
HClO4 = +4?
I have no idea if I'm doing these right. Can someone explain oxidation numbers and correct those?
Also can someone do an example in this and explain how they got it. I don't understand the concept.
Assign oxidation numbers to manganese in each of the following chemicals.
MnO4^2(aq)
Use oxidation numbers to identify the oxidation and reduction atoms
MnO4(aq) + H2Se(g) + H+(aq) > Se(s) + Mn2+(aq) + H2O(l)
Can someone please do those examples and explain how they got the answers because I don't understand oxidation numbers.

The first three equations are ok.
d) 2Al(g)+ Fe2O3(s) > 2Fe(l) + Al2O3(s)
oxidation  2Al >
Al goes from 0 oxidation state on the left to zero on the right so it is oxidized. Fe goes from +3 on the left to 0 on the right so it is reduced. I assume you can write the half equations.
have no idea what to do with the last one. If I made any mistakes or did anything wrong can someone correct them.
Oxidation Numbers
Assign oxidation numbers to chloride in each of the follow chemicals.
HCl = +1? No, H is +1 so Cl is 1
Cl2 = 0? right
NaClO = ? Na is +1, O is 2; therefore, Cl is what to make NaClO zero. Cl must be +1.
Cl = 1? right
HClO3 = either +1 or 3? H is +1, O is 2, there are 3 of them to make total on O of 6; therefore, what must Cl be to have HClO3 zero. Cl must be +5
ClO3 = 3? +5. O is 6 and Cl must be +5 to leave a 1 charge on the ion.
KClO2  +2? K is +1, O is 4, therefore, Cl must be +3
ClO2 = +2? Cl must be +4 to zero out the 4 from O2
HClO4 = +4? H is +1, O is 8; therefore, Cl must be +7
I have no idea if I'm doing these right. Can someone explain oxidation numbers and correct those?
Also can someone do an example in this and explain how they got it. I don't understand the concept.
Assign oxidation numbers to manganese in each of the following chemicals.
MnO4^2(aq) O is 8 so Mn must be +7 to leave a 1 charge on the ion.
Use oxidation numbers to identify the oxidation and reduction atoms
MnO4(aq) + H2Se(g) + H+(aq) > Se(s) + Mn2+(aq) + H2O(l)
Mn goes from +7 on the left to +2 on the right. Se goes from 2 on the left to 0 on the right.
Can someone please do those examples and explain how they got the answers because I don't understand oxidation numbers.
I think you have guessed at some of the answers and we don't want to do that, do we?. I think I have a good site with minimal rules that can clear this up for you if you want it. I hope I turned off the bold for your work and used bold for mine. If I didn't I assume you will know what you typed and what I typed, bold or not 
Minimal but simple rules to live by for redox. Oxidation numbers are nothing more than a book keeping method.
http://dbhs.wvusd.k12.ca.us/webdocs/Redox/MeaningofRedox.html
(Broken Link Removed)