Hey there!
Electrons are negatively charged and orbit the nucleus of the atom on energy levels (kind of in a cloud) :)
(The blue dots on the picture)
The answer is 75 minutes.
1.00*10^3
You’d need to lower the exponent because rounding to 3 sig figs changes the 9’s to - 1000. Keep the 0’s.
You could boil the liquid. If it is pure liquid than 100% of the liquid will boil off, however, if there is salt in the solution it will remain in the bottom of your beaker when the liquid has been boiled off.