Answer
$t = 197 s$
Work Step by Step
Use the formula
$ E= NE_{Ave}$
$ E = \frac{3.1g}{(63.54 g/mol)(6.022 \times 10^{23}/mol)} (\frac{3}{5}) (7.00 eV) (1.602 \times 10^{-19} J/eV)$
$E = 1.97 \times 10^4 J $
To calculate the time, we use the power equation
$P = \frac{E}{t}$
Rearrange the equation
$t = \frac{E}{P}$
substitute E and P from question.
$t = \frac{1.97 \times 10^4 J }{100 j/s}$
$t = 197 s$
