Candle in a Flask

Intro: Candle in a Flask

This is an inquiry based experience for chemistry students. Students are asked to make a prediction about what will happen with a scientific explanation for their prediction, then students are allowed to complete the activity and test their prediction.

Materials:
Erlenmeyer flask (I used 125 mL flasks)
dish to hold water in the base
candle
matches to light the candle
water with food coloring (helps the students see what is happening)
3 pennies

Fill the dish about half way with colored water. Light the candle and put in the center of the three pennies in the shallow dish. Balance the flask upside down on the three pennies in the shallow dish.

After students try the situation the first time, I encourage them to experiment with the situation to test their explanations about what is happening.

Comments

[Dream Dragon]

It's always cool to do hands on investigation with kids, and it doesn't have to be limited to lab equipment either, any reasonably heat proof jar and bowl will demonstrate the principle. I remember doing it with a measuring jug and mixing bowl. and realising that the water always reached the same level, prompting a discussion with my dad about the proportion of Nitrogen and Oxygen in the atmosphere.