Valentine’s Day Chemistry Activities

Sweetheart Challenge: Chemistry Conversation Hearts

Pastel-colored “conversation” hearts are a popular Valentine’s Day candy. Each small heart has a short and sweet message, like “Love ya”, “Chill out”, “Dream”, and “Be Mine”.

Challenge your club members to create chemistry-related conversation hearts.

Examples:

“Let’s react”
“I LuV U” (spell using element symbols)

Write the messages on hearts cut out of pastel-colored paper and display for a Valentine-themed bulletin board.

Eat Chocolate in the Name of Science

Try this simple experiment!

Break off two squares of a chocolate bar. Wrap each square in foil. Place one square in the freezer for a few hours and leave the other at room temperature.
Unwrap the room temperature square and place it on your tongue. How fast does the chocolate melt? How long does it take to taste the chocolate flavor?
Take a few sips of water or bites of an apple or saltine cracker to cleanse your palate.
Unwrap the square from the freezer and place it on your tongue. Is the experience the same as the room-temperature square?
Predict what would happen if you did the experiment again, but grated each square into small shavings first. Try it!

Explanation

This short experiment is based on Project 15: Viscosity and Flavour of "The Science of Chocolate" (second ed.) by Stephen T. Beckett (pp227-228).

The author explains "...the speed at which a food melts in the mouth affects its taste as well as its texture. This is because the chocolate viscosity affects the speeds at which the different molecules reach the flavor receptors." Students should notice a difference between the taste and texture of the room-temperature and frozen chocolate because the frozen chocolate must first be warmed up in the mouth before it melts, while the room-temperature chocolate quickly melts in the mouth. The difference in taste and texture of the frozen grated chocolate should be less because although it is still frozen, it melts more quickly on the tongue than a solid piece of frozen chocolate.

All About Chocolate

If you have suggestions on this topic, we would love to hear from you. Send your ideas to hschemclubs@acs.org