well, you need a volume to do that, so I have to assume a couple things here: 1) n refers to the number of molecules of KCl, and 2) 100 refers to milliliters. If this is true, then the solution is relatively simple:
x=number of moles in 100 ml = n/Avagadro's number,
y=number of liters = 100 ml/1000 ml
moles per liter is x/y. That is, whatever number of moles that the variable n represents, you have that many in 1/10 of a liter, so in a liter, you would have ten times that number of moles.
If you have a total of 0.1 moles of KCl in 100 ml, you have a concentration of 1 mole per liter.