Which reaction occurs at the cathode of a lead-storage battery that is discharging?

A. PbSO4 + 2H2O ---- 2e− + PbO2 + 4H+ + SO42−
B. 2e− + PbO2 + 4H+ + SO42− ---- PbSO4 + 2H2O
C. Pb + SO42− ---- PbSO4 + 2e−
D. PbSO4 + 2e− ---- Pb + SO42−

Question

Which reaction occurs at the cathode of a lead-storage battery that is discharging?

 A.	PbSO4 + 2H2O ----> 2e− + PbO2 + 4H+ + SO42−
 B.	2e− + PbO2 + 4H+ + SO42− ----> PbSO4 + 2H2O
 C.	Pb + SO42− ----> PbSO4 + 2e−
 D.	PbSO4 + 2e− ----> Pb + SO42−

vera_ewing · Answer

@JFraser D right?

jfraser · Answer

i don't know a whole lot about lead  batteries, but i'd say that looks reasonable

vera_ewing · Answer

@DanJS Do you know for sure if it's D? I can't miss this question....

danjs · Answer

the answer is on that page i linked in the other question you asked  about the Anode Half reaction.

danjs · Answer

Cathode 

PbO2 	+	3H +	+	HSO4−	+	2e −	 → 	PbSO4 	+	2H2O

danjs · Answer

reload page

vera_ewing · Answer

@DanJS I was having a really hard time understanding that stuff...can you check for me?

vera_ewing · Answer

@DanJS Sorry I was eating dinner. So the answer is B right?

danjs · Answer

i think so

vera_ewing · Answer

but you're not sure?

danjs · Answer

they took the H off of HSO4-   
and made 
4H+  +  SO4 -2    in the answer , compared to the one i pasted

danjs · Answer

it is the same thing

vera_ewing · Answer

thanks

danjs · Answer

the products are Lead Sulfate and water, only one choice B has those as the products