posted by alex .
15.0 mL of 8.00 M NaOH was diluted with water to 500 mL. Calculate the molarity
of the diluted NaOH solution.
0.015L x 8.00moles/1L x 39.997/1mole = 4.8g
M= (4.8g x 1mole/39.997) / 0.500L = 0.24M
is my workings correct? Is there another way to get to this?
It looks ok to me but there is an easier way to do it. If you use the dilution formula you don't need to change the units; just keep everything in mL.
The dilution formula is
mL1 x M1 = mL2 x M2
15 x 8.00 = 500 x M2 and
M2 = 15*8/500 = ?
Usually I don't use the dilution formula. If I know the dilution is from 15 to 500 I know the 8.00 M will be diluted by that factor; therefore,
8.00 x (15.0/500) = ?