My Science Box

When I suddenly fall ill, or otherwise don't want to take 10 hours to plan a sub lesson, I usually go online to http://puzzlemaker.school.discovery.com/ and plug in some vocab words for some puzzles (they have some pre-made banks of words also!)

I make four puzzles using the exact same list of words. I usually start them with the word search (even non-readers can do this!) then go on to word scramble, then crossword. This because they need to know the words pretty well by the time they get to the crossword - also, the word search has the word bank on it.

Summary
These experiments use a bell jar (or any other very large, clear, glass jar) to determine the identity of the gas produced by plants. It mirrors the famous experiments of Joseph Priestley and Jan Ingenhousz from the 1700’s that first demonstrated the existence of oxygen and its importance to plants and animals.

In 1771 and 1772, Priestly conducted a series of experiments using a bell jar. It was known that a candle placed in a sealed bell jar would eventually burn out and could not be relighted while still in the jar. Priestly discovered that a plant can survive indefinitely within a jar. Thus, he tried placing a plant into the jar with the burning candle. The candle went out as before and could not be relit right away. Priestly waited several days and tried again. The candle could be relit! The plant had restored the air inside the jar! (Do not try the next series of experiments since it harms animals!) Next priestly investigated what would happen to animals. He found that a mouse placed inside a sealed jar will eventually collapse. However, a mouse can survive in a sealed jar with a plant since the plant restores the air. Priestly was the first to demonstrate that oxygen is necessary for fire and animals but that given time, plants can create oxygen, allowing fires to burn and animals to breathe.