We Use Soap to Clean Ourselves Better Than We Could

question 50

Multiple Choice

We use soap to clean ourselves better than we could with water alone. Soaps contain phospholipids which are responsible for the cleansing action. Which of the following statements is the most likely explanation for how soaps work?

• A) Phospholipids are ions and therefore mix with both the water and oily dirt.
• B) Phospholipids are completely hydrophilic, and therefore oily dirt takes the place of the phospholipid molecules that would be dissolved in the rinse water.
• C) The phospholipid tail attaches to the oily dirt while the phospholipid head interacts with the rinse water and carries the dirt (and soap) away with it.
• D) The nonpolar fatty acid chains that make up the heads of the phospholipid are hydrophilic, and thus are repelled by the water.

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Definitions:

American System Of Manufactures

A system of production that relied on the mass production of interchangeable parts that could be rapidly assembled into standardized finished products. First perfected in Connecticut by clockmaker Eli Terry and by small-arms producer Eli Whitney in the 1840s and 1850s.

Interchangeable Parts

A manufacturing system where components are made to such precise standards that they can be swapped with similar parts in other assemblies without custom fitting.

Eli Terry

An American clockmaker from the early 19th century, known for his role in developing mass production techniques in clockmaking, significantly impacting the industry.

German Immigrants

Individuals from Germany who migrated to another country, significantly impacting the cultural and social composition of their new communities, especially in the 19th and early 20th centuries.