Download Viscosity Activity

Name: _______________________________________________ Date: ________ Period: _____
Viscosity Activity
Background: Viscosity is a liquid’s “resistance to flow”. All Lava is made
out of rock, but flows differently depending on silica content, amount of
water, gas content and temperature.
When lava erupts from a vent in the Earth’s crust it spreads out in all
directions and eventually cools and becomes a solid. Volcanoes may erupt
many times or only a couple of times. The repeated eruptions and lava
flows are what build the different landforms we see on earth’s surface.
Purpose: To investigate how the viscosity of lava will affect the type of
volcanic landform that is created.
Materials:
 3 paper plates
 3 paper cups, with a ¼ cup of flour in each
 1 Plastic spoon
 ruler
Procedure:
1. Label each plate; one is High Viscosity, one is Medium viscosity, the
last is Low Viscosity.
2. Next label the three cups, high, medium and low.
3. In the cup marked high, pour 30ml (about 2 Tablespoons) of water in
to the cup and mix well.
4. Slowly, pour the mixture on to the middle of the plate marked high
viscosity and make observations of how fast the mixture pours.
When the flow stops measure its diameter, in metric units.
5. In the medium cup slowly, pour 37ml (2 ½ tablespoon) water and
mix. Pour slowly onto the plate marked medium and record your
observations.
6. In the cup marked low viscosity slowly, pour 52 ml.
(3 ½ Tablespoons) water and mix. Pour slowly onto the plate marked
low viscosity and record your observations.
Data Chart A:
Viscosity
Describe how it
poured, speed, time,
etc.
Diameter of the
lava flow
What type of
landform will
this lava create.
High
Med
Low
Analysis:
1. How does viscosity affect the shape of volcanoes? Be specific, using
information from the activity.
2. What do you think would happen to the flow rate of the liquids if a
solid such as sand was added before pouring?
3. How would this relate to a composite volcano?
4. Describe the 3 main types of volcanoes based upon the viscosity of
the eruption.
Conclusion: Sum up the learning of this unit experience. Explain
viscosity. How is this related to volcanoes? How are the 3 types of
volcanoes formed with regards to viscosity?