Electrochemistry
Consider the following electrochemical cell:
Cd(s) | Cd2+(aq) || Ce4+(aq) ; Ce3+(aq) | Pt(s)
What would increasing the concentration of Ce3+(aq) do to the cell potential
decrease it
What is the oxidation state of the Cr atom in the molecule K2CrO4?
It is well known that when salt is dissolved in water, the temperature drops. Knowing this, what could be the contributing factor for the spontaniety?
(a) enthalpy
(b) entropy
(c) both a and B
(d) um physics
b
A large electrolysis cell is capable of producing metallic uranium from the oxide ore UO2. It can produce 47.50 kg of U (238.029 g/mol) in 24.00 hours. What current must it be delivering to produce this amount of U?
When the half-cell represented by:
PbO2(s) | PbO(s) | OH-(aq)
is functioning as a cathode in a cell, what is the balanced half reaction that is occurring
PbO2(s) + H2O(l) + 2e- --> PbO(s) + 2OH-(aq)
An electroplating solution contains vanadium (50.9415 g/mol), which is a metallic element that can exist in solution in at least 4 oxidation states. A current of 1.50 A operates on the electrolysis cell for 30.0 minutes. During this time, 0.285g of V is deposited on the cathode. What is the oxidation state of the vanadium in solution?
+5
One of the many important atmospheric reactions involving nitrogen oxides is this one:
N2O(g) + 0.5 O2 <--> 2 NO(g)
At 298 K, the equilibrium constant is 5.05 x 10-13. Under conditions where P(N2O) = 3.00 atm, P(O2) = 10.00 atm, and P(NO) = 9.00 x 10-6 atm, what is the value for the Gibbs energy of reaction in kJ/mol?
7.0
Balance the following equation in acidic solution:
H2O2(aq) + Ti2+(aq) --> Ti4+(aq) + H2O(l)
If, in the balanced equation, the coefficient for Ti2+(aq) is 1, what is the coefficient for H+(aq)?
2
A concentration cell is set up with 2 nickel electrodes and 2 solutions of Ni(NO3)2. One cell contains a solution that is 0.870 M and we connect that electrode to the positive terminal of a voltmeter. The other solution is 0.000205 M and is connected to the negative terminal. The measured voltage on the voltmeter is positive. at 298K, what is that measured positive potential?
0.107
In the following, which species is oxidized?
3 Ag2S(s) + 8 H+(aq) +2 NO3-(aq) --> 6 Ag+(aq) + 3 S(s) + 2 NO(g) + 4 H2O(l)
Ag2S
A chemical reaction system is represented by this equation:
Ag(s) + Br + Fe3+(aq) --> Fe2+(aq) + AgBr(s)
The standard reduction potentials at 298 K for AgBr//Ag = 0.323 V and for Fe3+/Fe2+ = 0.463 V. What is the value fo the equilibrium constant K at this temperature?
233
The initial concentration of a reactant in a first-order reaction is 0.64 mol/L. The half-life of the reaction is 30.0 seconds
1. calculate the concentration of the reactant 60.0 seconds after the initiation of the reaction
AND
2. How long would it take for the concentration of the reactant to drop to 0.040 mol/L
1. 0.16 M
2. 120 seconds
A cell is set up based upon these iron and coper redox couples: Cu/Cu2+ and Fe/Fe2+. Copper behaves as the cathode and when properly connected to a voltmeter, the standard cell potential is E° = +0.789V. The concentration of copper ion is 1.00M. The Fe2+ concentration is not known but the measured voltage is +(8.36x10-1) V. At 298K, what is the [Fe2+] in the anode compartment?
2.58 x 10-2 M
2OH−(aq)+2 Ag(s)+ Zn2+(aq)→Zn(s)+Ag2O(aq) +H2O
Calculate ∆rG° for the following reaction at 298K as written:
2 Ag(s) + Sn4+(aq) --> 2 Ag+(aq) + Sn2+(aq)
The standard reduction potentials are Ag+/Ag = 0.861 V and Sn4+/Sn2+ = 0.139 V
139.3 kJ/mol
What is the name of my cat?