Answer:
Last option 19.6 g
Explanation:
In order to do this, we need to apply the Faraday law which is the following:
q = I*t (1)
Where:
I: current in Amperius
t: time in seconds
q: charge in Coulombs
the time in seconds is:
t = 33.5 min * 60 s/min = 2,010 s
Replacing in (1):
q = 8.7 * 2,010 = 17,487 C
With this value, we need to calculate the moles of Ag. This can be done dividing this value with the respective charge in one mole:
moles = q/n
n: value of 1 mole of electron / C = 96500 C/mol e
Replacing we have:
moles = 17.487 / 96,500
moles = 0,1812 moles e
Remember now that each mole of Ag+ can only catch one electron at a time, so, 0.1812 moles e, would be 0.1812 moles.
Finally, we need the molecular mass of Ag, which is 107.87 g/mol so:
m = 0.1812 * 107.87
m = 19.55 g or 19.6 g
