Find the initial pH of the NaOH solution (strong base).
pOH= -log [OH-]= -log[0.01]= 2
pH= 14-pOH= 14-2= 12
Solve for moles NaOH:
(100 mL= 0.1 L)
0.01M NaOH= x moles NaOH/ 0.1 L
x moles NaOH= 0.001 mol NaOH
Now solve for new concentration with 1 L (NOTE: Moles NaOH does not change):
0.001 mole NaOH/ 1 L= 0.001 M
Solve for new pH:
pOH= -log [OH-]= -log[0.001]= 3
pH= 14-pOH= 14-3= 11
Easy way: pH works on logorithmic scale. When you dilute something by 10 times (100 mL to 1000 mL), you're moving down by one pH.
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