Achieve #17

[KyLee 1H]

Can someone walk me through #17?
What would the potential of a standard hydrogen electrode (S.H.E.) be under the given conditions?
[H] = .37 M PH2 = 2.9 atm T = 298K

[Antonia Valencia 2H]

Hi! In order to solve this equation you have to use the Nernst equation, E = Eo - (0.05916V)/n (logQ). Firstly, we have to consider the reduction reaction of SHE: 2H+(aq)+2e<−−>H2(g). For this equation, the Eo value is 0. Moreover, this equation tells us that n, the number of electrons being transferred, is 0. Next, in order to solve for Q, you have to use the given pressure of H2 and divide that by the concentration of H squared. In other words, Q = PH2 / [H]^2 or Q = (2.9)/(.37)^2. Finally, you plug all these values into your calculator and you should get your answer. I hope this helps!

[Mona Reddy Kurra 1J]

Hi! Another way to solve this equation is using the Nernst equation in the form E = Eº - RT/nF lnQ, where Q is based on the new concentration and partial pressure values. One important thing to note is that you need to consider the coefficients when determining the value of Q. I hope that helps!

[Ginny Ghang 1B]

You can use the Nernst equation here (E = standard cell potential - RT/nF * lnQ. The standard cell potential is equal 0V for a S.H.E. Use the given concentrations/pressure to find Q, make sure to convert the temperature to Kelvin, and n is equal to the coefficient in front of your electrons (the number of electrons transferred). Plug these values in and solve for E.

[Sydney Ngao 3I]

We would use the nernst equation formula to plug in what we know and it gives us the E nought/standard is 0 so it would be 0 for that term. T needs to be in Kelvin and n is the number of electrons involved and F and R are constants. We can find Q based on the concentration and partial pressure that it gives us.

[Jennifer Kainth 3L]

This problem might be solved using the Nernst equation, E = Eº - RT/nF lnQ.
Q will be dependent on the new concentration and partial pressure values. I
While calculating the value of Q, the coefficients should also be taken into account. I hope this was helpful!

[Sara Dolmo 2J]

For this homework problem, I used the Nernst equation E = Eº - 0.0592/n logQ. You find Q by dividing the new concentration and partial pressure values. Then you add the information that you found into the equation to find your answer.

[Allen Lu 2F]

Because we are looking at a standard hydrogen electrode, we know that we can use the following derivation of the Nernst equation: E = - 0.0592/n logQ. This is because it is at standard temperature and Eo = 0 under SHE conditions. We also know from the equation that 2 electrons are transferred so the equation would be set up as follows: E = - 0.0592/2 * log[(2.9)/(.37)^2] = -0.039.

[LukeYing_3H]

You can use Nernst's equation with E0=0 and using the given concentrations to find Q and then solve for Ecell.

[Raizel Ferrer 1H]

You can use the Nernst equation E = Eº - 0.0592/n logQ to solve this problem! I made E0 = 0 because the system is under S.H.E. To find Q, I wrote out the reduction 1/2 reaction. Q = atm/[M] so I plugged in the pressure and molarity of H+ into the equation to find Q at that point. I then plugged in Q back into the Nernst equation to solve for E.