A DIALOGUE WITH SARAH, AGED 3: IN WHICH IT IS SHOWN THAT IF YOUR DAD IS A CHEMISTRY PROFESSOR, ASKING "WHY" CAN BE DANGEROUS
By Stephen McNeil
-From the archives-
SARAH: Daddy, were you in the shower?
DAD: Yes, I was in the shower.
SARAH: Why?
DAD: I was dirty. The shower gets me clean.
SARAH: Why?
DAD: Why does the shower get me clean?
SARAH: Yes.
DAD: Because the water washes the dirt away when I use soap.
SARAH: Why?
DAD: Why do I use soap?
SARAH: Yes.
DAD: Because the soap grabs the dirt and lets the water wash it off.
SARAH: Why?
DAD: Why does the soap grab the dirt?
SARAH: Yes.
DAD: Because soap is a surfactant.
SARAH: Why?
DAD: Why is soap a surfactant?
SARAH: Yes.
DAD: That is an EXCELLENT question. Soap is a surfactant because it forms water-soluble micelles that trap the otherwise insoluble dirt and oil particles.
SARAH: Why?
DAD: Why does soap form micelles?
SARAH: Yes.
DAD: Soap molecules are long chains with a polar, hydrophilic head and a non-polar, hydrophobic tail. Can you say 'hydrophilic'?
SARAH: Aidrofawwic
DAD: And can you say 'hydrophobic'?
SARAH: Aidrofawwic
DAD: Excellent! The word 'hydrophobic' means that it avoids water.
SARAH: Why?
DAD: Why does it mean that?
SARAH: Yes.
DAD: It's Greek! 'Hydro' means water and 'phobic' means 'fear of'. 'Phobos' is fear. So 'hydrophobic' means 'afraid of water'.
SARAH: Like a monster?
DAD: You mean, like being afraid of a monster?
SARAH: Yes.
DAD: A scary monster, sure. If you were afraid of a monster, a Greek person would say you were gorgophobic.
(pause)
SARAH: (rolls her eyes) I thought we were talking about soap.
DAD: We are talking about soap.
(longish pause)
SARAH: Why?
DAD: Why do the molecules have a hydrophilic head and a hydrophobic tail?
SARAH: Yes.
DAD: Because...
By Stephen McNeil
-From the archives-
SARAH: Daddy, were you in the shower?
DAD: Yes, I was in the shower.
SARAH: Why?
DAD: I was dirty. The shower gets me clean.
SARAH: Why?
DAD: Why does the shower get me clean?
SARAH: Yes.
DAD: Because the water washes the dirt away when I use soap.
SARAH: Why?
DAD: Why do I use soap?
SARAH: Yes.
DAD: Because the soap grabs the dirt and lets the water wash it off.
SARAH: Why?
DAD: Why does the soap grab the dirt?
SARAH: Yes.
DAD: Because soap is a surfactant.
SARAH: Why?
DAD: Why is soap a surfactant?
SARAH: Yes.
DAD: That is an EXCELLENT question. Soap is a surfactant because it forms water-soluble micelles that trap the otherwise insoluble dirt and oil particles.
SARAH: Why?
DAD: Why does soap form micelles?
SARAH: Yes.
DAD: Soap molecules are long chains with a polar, hydrophilic head and a non-polar, hydrophobic tail. Can you say 'hydrophilic'?
SARAH: Aidrofawwic
DAD: And can you say 'hydrophobic'?
SARAH: Aidrofawwic
DAD: Excellent! The word 'hydrophobic' means that it avoids water.
SARAH: Why?
DAD: Why does it mean that?
SARAH: Yes.
DAD: It's Greek! 'Hydro' means water and 'phobic' means 'fear of'. 'Phobos' is fear. So 'hydrophobic' means 'afraid of water'.
SARAH: Like a monster?
DAD: You mean, like being afraid of a monster?
SARAH: Yes.
DAD: A scary monster, sure. If you were afraid of a monster, a Greek person would say you were gorgophobic.
(pause)
SARAH: (rolls her eyes) I thought we were talking about soap.
DAD: We are talking about soap.
(longish pause)
SARAH: Why?
DAD: Why do the molecules have a hydrophilic head and a hydrophobic tail?
SARAH: Yes.
DAD: Because...















Lison