1. WELCOME TO
OUR SCIENCE
CLASS!

3. Activity 1: ANALYZE ME!

4. Activity 1: ANALYZE ME!

5. Activity 1: ANALYZE ME!

6. Primary factors
affecting volcanoes’
eruptive style

7. At the end of the discussion, the
students can:
a. identify the Primary factors
affecting volcanoes’ eruptive style

8. b. describe the Primary factors
affecting volcanoes’ eruptive style
c. perform the pressure me through
experiment.

10. 1. Get and shake a sealed carbonated
beverage(Coke,Sprite,Pepsi, Orange,
Royal) can (or bottle) for seconds.
2. Open 1 can in less than one second.
3. Open the other slowly taking 30
seconds.

11. 1. What happened when you opened
the can quickly (in less than one
second)?
2. What happened when you opened
the can slowly (taking 30 seconds)?

12. 1. The magmas’
temperature
•The hotter the temperature of
magma is, the lower its
viscosity the more rapidly it
flows.

13. 2. It’s chemical composition
• Magma’s resistance to flow is a
function of its “internal friction”
derived from the generation of
chemical bonds within the liquid.

14. 3. The number of dissolved
gasses it contains
•All magmas contain gasses that give
their explosive character the gas will
increase as pressure reduces.

19. •Pick one primary factors affecting volcanoes’
eruptive style from a folded paper.
Criteria:
Content- 10%
Presentation-
5%
Teamwork-
5%

20. QUIZ:
Pat I. Enumeration
1-3 Give the Primary factors affecting volcanoes’
eruptive style.

21. Part II. True or False
1. Magmas with high silica content are more viscous than
those with low silica content.
2. The hotter the temperature of magma is, the higher its
viscosity the more rapidly it flows.
3. Magma’s resistance to flow is a function of its “internal
friction” derived from the generation of chemical bonds
within the liquid.
4. The amount of liquid contained in the magma affects its
viscosity but in a more mysterious way than temperature
and silica content.
5. The viscosity of the residual liquid will increase as gas
escapes.