Who deposits first, in code

You will write functions that decide which ion deposits first at a cathode, how much of it is left when the next one starts, and whether hydrogen would win. The checker tests them with new numbers.

The idea. The deposition potential of an ion is $E^\circ + \dfrac{0.0591\ \text{V}}{n}\log c$. The ion with the highest value goes first. When the second ion starts, the first ion has a concentration $c$ at which $E^\circ_1 + \dfrac{0.0591\ \text{V}}{n_1}\log c$ equals the starting potential of the second. Hydrogen forms at $-0.0591\ \text{V} \times \text{pH} - \eta$.

Your tasks.

1. Complete deposition_potential(e0, n, conc) so that it returns the potential in volts.
2. Complete first_to_deposit(ions). The argument is a dictionary {name: (e0, n, conc)}. Return the name of the ion with the highest deposition potential.
3. Complete share_left(first, second). Each argument is a tuple (e0, n, conc). Return the percentage of the first ion that is left when the second ion starts to deposit.
4. Complete hydrogen_first(e_metal, ph, eta) so that it returns True when the working potential of hydrogen is above the deposition potential of the metal.