Consider a galvanic cell based on the following two half reactions at 298 K: SRP Fe3+ + e- Fe2+ 0.77 V Cu2+ + 2 e- Cu 0.34 V How many of the following changes will increase the potential of the cell? Why?
1. Increasing the concentration of Fe+3 ions
2. Increasing the concentration of Cu2+ ions
3. Removing equal volumes of water in both half reactions through evaporation
4. Increasing the concentration of Fe2+ ions
5. Adding a NO3 - solution to the anode portion of the cell
In: Chemistry
1. Prepare 1 mmol/L Lithium standard from lithium carbonate (Li2CO3). Give the quantity in mg/L.
2. If 3 mL of a 100 mcg/mL is diluted to 100 mL. What is the concentration in mg/dL?
3. Prepare 1L of 0.06M NaOH (FW 40) solution from 1N stock solution.
4. Prepare 2L of 0.85% (W/V) NaCl (FW 58).
5. Prepare a 5% W/V calcium chloride solution from CaCl2 * 6H2O (FW 219).
In: Chemistry
Determine the thermodynamic state of 1,1,1,2-Tetrafluoroethane (R-134a) at 102 °C and 1000 kPa. Critical Pressure= 4.059 MPa, Critical Temperature = 101.06°C.
*I keep getting stuck with a quadratic equation and two volume values, when using the van der Waals equation of state (P=(RT/(V-b))-(a/V^2))....I am determining the thermodynamic state by finding if the compressibility factor (z) is less than or greater than 1, to find if attractive or repulsive forces dominate.
In: Other
Calculate the equilibrium potential of a copper wire immersed in 0.0005 M CuSO4 solution. The standard electrode potential for the reaction Cu2+ + 2e- = Cu0 at 25°C is 0.34 V (NHE). Now, answer the following questions and enter your results (numerical number only). Calculate the ionic strength (M) of the solution. 2.0×10-3 You are correct. Calculate the activity coefficient of Cu2+. 0.82 You are correct. Calculate the equilibrium potential (v) of the copper wire electrode. Note: use activity instead of concentration.
In: Chemistry
A piston–cylinder device initially contains 2 kg water in 1 m3 at 500 kPa. The system then cools down and the volume drops to half and pressure of 300 kPa. At this state, the piston is resting on a set of stops, and the mass of the piston is such that a pressure of 500 kPa is required to move it. (a) Show the process on a P-v, T-v and P-T diagrams with respect to saturation lines and determine, (b) the final temperature, (c) the work done during this process, and (d) the total heat transfer. full step plz
In: Mechanical Engineering
Consider the following standard reduction potentials,
For the voltaic cell reaction below, calculate the Fe2+ concentration that would be needed to produce a cell potential equal to 0.16 V at 25 oC when the pH of the solution is 13.00, [Fe3+] = 0.50 M and [H2O2] = 0.35 M.
|
Half Reaction |
Eo (V) |
|
Fe3+(aq) + e‒ → Fe2+(aq) |
0.77 |
|
H2O2(aq) + 2 e‒ → 2 OH‒(aq) |
0.88 |
2 Fe2+(aq) + H2O2(aq) → 2 Fe3+(aq) + 2 OH‒(aq)
In: Chemistry
1. Calculate the permeability of electrons with energy of 0.1 eV
and 0.5 eV respectively when penetrating a positional energy
barrier of 1.0 eV in height and 100 pm in length by tunnel
phenomenon.
k Attachment image=[2m(V-E)]^1/2
T={1+(e^kL-e^-kL)^2/16ε(1-ε)}^-1 (ε= E/V)
2. Explain the meaning of tunneling covered in the above problem
with the wave and explain the difference between classical and
quantum mechanics based on it.
In: Physics
16. Which of the following statements is false?
(a) Let S = {v1, v2, . . . , vm} be a subset of a vector space V with dim(V) = n. If m > n, then S is linearly dependent.
(b) If A is an m × n matrix, then dim Nul A = n.
(c) If B is a basis for some finite-dimensional vector space W, then the change of coordinates matrix PB is always invertible.
(d) dim(R17) = 17.
(e) If B1 and B2 are both bases for the same vector space, then B1 and B2 have the same number of vectors.
In: Advanced Math
1)What potential difference is needed to stop an electron that has an initial velocity v=7.0×105m/sv=7.0×105m/s?
2)How strong is the electric field between the plates of a 0.80-μFμF air-gap capacitor if they are 3.0 mmmm apart and each has a charge of 72 μCμC ?
3)A 3700-pFpF air-gap capacitor is connected to a 30-V battery.If a piece of mica (K= 7) is placed between the plates, how much charge will flow from the battery?
In: Physics
How to shorten this "if-else" statements in R studio? Thank you sooo much!
fizzbuzz = function(v = NULL){
for (term in v){
if (is.infinite(term) != TRUE){
if (is.numeric(term)){
if (term == as.integer(term)){
if (term %% 3 == 0){
if (term %% 5 == 0){
print("FizzBuzz")}
else {
print("Fizz")
}
}
else if (term %% 5 == 0){
print("Buzz")
}
else {
print(term)
}
}
else {
print ("This number is not an integer.")
}
}
else {
print ("This is not a number, or this number was entered as a
string.")
}
}
else {
print ("You must enter an integer for this function to
work.")
}
}
}
In: Computer Science