Electrochemical cell series question?
hi...... a) what reaction ??....you have not mentioned any reaction b)you have not mentioned the temperature so i am assuming it as 25 degree C or 298 K disproportion means Cu+ is oxidised as well as well as reduced ... 2Cu+ --------> Cu + Cu2+ it can be thought of following two half reactions ... Cu+ + e- --------> Cu since this is reduction so it will take place at cathode .....and Eo(cathode) = 0.52 V and another half reaction will be ... Cu+ --------> Cu2+ + e- since this is oxidation so it will take place at anode .....and Eo(anode) = 0.16 V and Eo(cell) = Eo(cathode) - Eo(anode) = 0.52 - 0.16 = 0.36 V as i told earlier ...always use reduction potential data ....no change of sign is recquired ... and equilibrium constant K is related to Eo(cell) by the following relation ... Eo(cell) = 2.303RT/nF log K where R = 8.314 J/K/mole T = 298 K n = no.of electrons participating = 1 F = 96500 C putting the values... 0.36 = 2.303 X 8.314 X 298 / 96500 X log K 0.36 = 0.0591 X log K log K = 0.36/0.0591 = 6.0913 taking antilog ... K = 10^6.0913 = 1.233 X 10^6 c) are you sure that you have written the question correctly ?? it should be calculate the equilibrium concentration of Cu2+ please add additional details for a) and c) or mail me
Electrochemical cells question?
The electrolysis of the NaI/water solution will produce iodine at the anode. Iodine will react with the starch to give a blue color. Another reaction product is OH- formed at the cathode by reduction of the water. This will cause the phenolphthalein to give a purple color. Iodine will react with NaOH to give NaOI. In general, electroplating of metals works much better (gives a more even finish) if a complexation reagent is in the solution. Ammonia is fairly economical but some others work better.
Chemistry Lab Question on Electrochemical Cells?
Assume the cell potential from part a is the same as the standard cell potential for your ascorbic acid cell. What would the cell potential be if the copper electrode was replaced with the standard hydrogen electrode for the pH 5 cell? Hint: Think about which was the reference (anode). My part a was .188 V Thanks so much!
Use the information given below to answer the questions about this standard electrochemical cell?
Since the Cu2+/Cu half cell has a higher reduction potential (+0.34 V) than the Zn2+/Zn electrode (-0.76V), the reduction reaction would be: Cu2+(aq) + 2 e- → Cu (s) And the oxidation reaction would be: Zn (s) -→Zn2+(aq) + 2 e- (the flip of the above). The overall reaction would be the two added together Cu2+ (aq) + Zn(s) --> Cu(s) + Zn2+(aq). Let's use this equation to answer our question. 1. False. Cu2+ is a reactant. 2. True. Negatively charged ions (called anions) ALWAYS flow to the anode. (Anion, anode, should be easy to remember!) 3. True. Cu2+ is a reactant, therefore it will be consumed during the reaction and the concentration will decrease. 4. True. Anode is the site of oxidation. Since the oxidation reaction consumes Zn(s) to make Zn2+(aq), the mass of Zn will decrease. 5. False. Electrons always flow from anode to cathode. Hope this helps, Jackie
Electrochemical cell chemistry question help!!!?
1) An electrochemical cell has an Eocell of 1.10 V and transfers 2 moles of electrons. - What is the value of delta G; in kJ/mol? 2) Identify the battery (Button,Dry Cell,Automobile) that uses each of the following half-reactions: a) Ag2O + H2O + (2e)1- -> 2Ag + (2OH)1- b) 2MnO2 + H2O + (2e)1- -> Mn2O3 + (2OH)1- c) Pb + SO42- -> PbSO4 + (2e)1- 3) Indicate whether each reaction could form the basis of a galvanic cell or require an electrolytic cell to be accomplished. a) Cu + Ni2+ -> Cu2+ + Ni b) 2H2O -> 2H2 + O2 c) 2Na + Cl2 -> 2NaCl i really need some help....thanks
Chemistry question regarding electrochemical cells?
Answer is A. Positive std cell potential means DeltaG^o is negative, i.e. reaction is spontaneous in forward direction. Since DeltaG^o=-RTlnK, a negative DeltaG^o means lnK>0, which in turn means that K>1, The negative cell potential means DeltaG is positive, i.e. reaction is not spontaneous in forward direction. Since DeltaG=DeltaG^o+RTlnQ =-RTlnK+RTlnQ =RT(-lnK+lnQ) =RTln(Q/K). DeltaG can only be positive if ln(Q/K)>0, which in turn means that Q/K>1. Rearranging the inequality gives Q>K.
What are some unanswered questions in electrochemical engineering?
In my narrow, applied subfield, the critical questions are: Why do electrocatalysts (especially for hydrogen oxidation) show different activity in base and in acid? And -- more puzzling -- why do they show different activity in solid and liquid electrolytes of the same pH (to the extent pH is defined for a solid)?
Electrochemistry - General questions about a Voltaic Cell ?
a voltaic cell: oxidation @ the anode (-): Zn --> Zn+2 & 2 e- reduction @ cathode (+): Cu+2 & 2e- --> Cu ======================================... Mark each of these statements as True or False. -Negatively charged ions flow from the salt bridge to the anode. True -The concentration of Zn2+ decreases as the reaction proceeds. False -Cu2+ is a reactant of this overall reaction. False -The electrons will flow from the cathode to the anode. False -The solid metal cathode decreases in mass. False check out this video & click on areas of interest: http://www.mhhe.com/physsci/chemistry/es...
What are electrochemistry cells?
cells where chemical reactions produce electricity(dry cell) or electric current conducts chemical reactions(daniel cell) are called electrochemical cells.