Science Buddies: "Ask an Expert"

my son is doing a project on the harshness of soap.
I know you can test the ph level of sodium hydroxide with Phenolphthalein (phenol p) on homemade soap.. could that be the same to test on over the counter body soap? (zest, dove, dial, tone, etc)

yes, Phenolphthalein (phenol p) can be tested with any substance whether homemade soap or over the counter body soap

I hope that helps!

Kayli Masuda

thank you. I wasn't sure. this can be a little indicator of what soaps may be harsher than others, even if the presence of skin irritation is mild, or even unnoticeable.

do i just put a drop of the phonol on the soap. i didn't see a color change. should it be mixed with water or the lye in the soap isn't strong enough to pick up a color change.

please advise