Re: If you add a base (soap pH 6.3) to a neutral( water) is it a weaker base???

Hi Emily:

Let's define a few vocabulary words aften associated with acids and bases. 
 First of all strong and weak do not refer to how badly they will "burn" 
you or hurt you.  Strong and weak refers to how well an acid or a base will 
dissociate (break apart) in water and produce H+ (for acids) and OH- (for 
bases).  if an acid dissociates well, it is considered strong.  If an acid 
or base does not dissociate well, it is considered weak.  Concentrated and 
dilute are two other words.  Concentrated refers to how many H+ and OH- 
there are in solution.  for example,  you have a high concentration of hair 
on your head, but not so much on your feet (I hope!).  So you can have a 
weak solution of a strong base, and conversely, a concentrated solution of 
a weak base.  Now to answer your question-->  the water cannot weaken the 
base.  The water can dilute the base, or make the base less concentrated.  
Just like if you added a bunch of water to a glass of Kool-Aid.  If you add 
a lot of water to a small amount of base, you shift the pH to be more like 
that of water, which is approximately 7.  

Soaps are made from fats and strong bases such as lye (sodium 
hydroxide).  Because of this, most soaps are basic, which means their pH is 
above 7.

reference:

CHEMISTRY, THE CENTRAL SCIENCE, Brown and LeMay, Prentice Hall, 8th 
edition, 2000, pp 114-115.