Yellow-Jellow

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nedddddddd help in balancing equations

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hi everybody...i really have a lot of trouple balancing equations in acidic and basic conditions so i need your help in these ...thanx alot !! .. ...

balance the following in acidic conitions

1) Br2(l) + SO2(g) -----> Br-(aq) + SO4 2- (aq)



2) Cu(s) + NO3 - (aq)------> Cu2+ (aq) + NO(g)



3) PbO2(s) + Cl- (aq) -----> PbCl2(s) + Cl2 (g) ( balance Cl in both half-reactions)



4) Cl2(g) --------> ClO3 - (aq) + Cl- (aq) (same reactant in each half-reaction)



Balance the following in basic conditions



5) N2H4(aq) + Cu(OH)2 (S) ------> N2(g) + Cu(s)



6) MnO4 - (aq) + NO2 - (g) -------> MnO2(S) + NO3 - (aq)



7) Cr(OH)3 (s) + H2O2(aq) --------> CrO4 2- (aq) + H2O (aq)



8) Al(s) + NO3 - (aq) --------> Al(OH)4 - (aq) + NH3(aq)



also i like to know what is the half-reaction methode and how can i do it..thanx alot for the help!!
 

Abilene

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Yellow-Jellow said:
nedddddddd help in balancing equations

--------------------------------------------------------------------------------

hi everybody...i really have a lot of trouple balancing equations in acidic and basic conditions so i need your help in these ...thanx alot !! .. ...

balance the following in acidic conitions

1) Br2(l) + SO2(g) -----> Br-(aq) + SO4 2- (aq)



2) Cu(s) + NO3 - (aq)------> Cu2+ (aq) + NO(g)



3) PbO2(s) + Cl- (aq) -----> PbCl2(s) + Cl2 (g) ( balance Cl in both half-reactions)



4) Cl2(g) --------> ClO3 - (aq) + Cl- (aq) (same reactant in each half-reaction)



Balance the following in basic conditions



5) N2H4(aq) + Cu(OH)2 (S) ------> N2(g) + Cu(s)



6) MnO4 - (aq) + NO2 - (g) -------> MnO2(S) + NO3 - (aq)



7) Cr(OH)3 (s) + H2O2(aq) --------> CrO4 2- (aq) + H2O (aq)



8) Al(s) + NO3 - (aq) --------> Al(OH)4 - (aq) + NH3(aq)



also i like to know what is the half-reaction methode and how can i do it..thanx alot for the help!!
6)(1/2)MnO4- + NO2- = (1/2)MnO2 + NO3-
that's all for now...if i figure out the others, I'd let you know.
 

DrEaMeRcHiCk

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do u want the answers to these or do u need help knowing how to do them? Because I'm currently learning this stuff right now and they're not that bad just takes practice. If you need to learn how to do them...ask me becuz the best way to learn these is to do lots of them....then you automatically see what's being reduced/oxidized and when to put in H20 (you use this to balance O) and for acidic you use H+ to balance Hs and for basic solutions you use OH- to balance...i had problems with these too but just keep working on them...=)
 

Requiem

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Yellow-Jellow said:
nedddddddd help in balancing equations

--------------------------------------------------------------------------------

hi everybody...i really have a lot of trouple balancing equations in acidic and basic conditions so i need your help in these ...thanx alot !! .. ...

balance the following in acidic conitions

1) Br2(l) + SO2(g) -----> Br-(aq) + SO4 2- (aq)



2) Cu(s) + NO3 - (aq)------> Cu2+ (aq) + NO(g)
Here's how I'd do this:
Cu(s) -> Cu(2+) + 2e- x3
NO3 + 3 e- + 4 H+ -> NO + 2 H2O x2

3Cu + 2NO3- + 6e- + 8H+ -> 3 Cu(2+) + 6e- + 2NO + 4H20

3Cu + 2NO3- + 8H+ -> 3Cu(2+) + 2NO + 4H20
Total charge: 6+ = 6+
That should be correct.


General Chemistry come back to me! :p
In basic solution there's one extra step. Notice how there's 8 H+ ions there, you'd add 8OH- to both sides to make water and excess OH- on one side.

So you'd get it
3Cu + 2NO3- + 8H20 -> 3Cu2+ + 2NO + 4H20 + 8OH-