Construct a model volcano, mix household chemicals to represent
lava, and combine this mixture with another household chemical
to cause a volcanic eruption. (This works especially well outside.)
What You Need:
Baking soda - 4 tablespoons
Board - about 20" square (optional)
Dish detergent, clear - ½ cup
Jar, 1 quart (1 litre)
Jar, small (e.g. baby food jar)
Measuring cup and tablespoon
Vinegar - ¼ cup
Water - ½ cup
Food colouring, red - 1 bottle per class |
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What
To Do:
Make
a mountain shape out of dirt. If students wish to repeat
the eruption, provide plaster of Paris rather than dirt.
The plaster of Paris version will be more permanent. Follow
instructions on box. If a group wishes to keeps its volcano,
they should build it on a wooden board.
Bury a small jar in the top of the mountain just to the
top of the jar. Do not cover the jar.
Put 4 tablespoons of baking soda into the small jar buried
to the rim in the mountain.
Mix the water, dish detergent and the vinegar in the quart
jar. Add a drop or two of the food colour to each group's
quart jar. (This recipe has enough ingredients for several
eruptions.)
Pour a small amount of the mixture into the small jar
in the mountain. Observe carefully the eruption that occurs.
You may need to help the reaction along by stirring inside
the volcano with a stick.
What's
Going On?
Baking
soda and vinegar, when mixed with together in a small
jar, produces carbon dioxide gas. If dish detergent is
mixed with the vinegar, the gas creates bubbles. If food
colouring is also added to the vinegar, the substance
produced looks somewhat like red-hot molten lava. The
gas in the mixture forces the bubbles (lava) out of the
opening of the small jar.
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