Using Faraday's laws of electrolysis, calculate the number of moles (N) of a substance deposited with a valency (z) of 2, given a current (I) of 3 A for a time (t) of 400 s.

Here's the solution based on the parameters provided in the image. The question "NE?" is interpreted as asking for the number of moles ($N$) of the substance deposited.

Given Parameters from the image:

• Time ($t$) = 400 s
• Current ($I$) = 3 A
• Valency ($z$) = 2 (This is the number of electrons per mole of substance)
• Faraday's constant ($F$) = 96500 C/mol
• Relative Atomic Mass ($\text{RAM}$) = 119 g/mol (This parameter is not needed to calculate $N$ using the current and time, but would be used if calculating mass deposited).

Formula to calculate moles ($N$) from current and time:

$$N = \frac{I \times t}{z \times F}$$