Untitled Flashcards Set

What is the difference between geocentric and heliocentric? Geo has earth at the center of the universe while helio has the sun at the center.

What does understanding that difference tell us about how we look at

new scientific ideas?

Know the planets, in order. Mercury, Venus, earth, Mars Jupiter Saturn Uranus Neptune

What is the difference between a hypothesis, a theory, and a scientific

law?  A hypothesis is a proposed explanation a theory is a well established explanation supported by evidence and scientific law is a statement describing a consistent pattern in nature.

What features of Mars suggest that it might be a better place to visit

someday? It has water in the form of ice

Where in the solar system would you look for life? Why? Th moon of Saturn shares chareteristics we need to live

Proton a stable particle with positive charge

Electron a negatively charged particle that circles the atom

Neutron a particle found inside the nucleus is neutrally charged

Atomic number the number of protons in a nucleus

Atomic weight the total weight of the atom

Isotope a variation of a atom that has same number of protons but different number of neutrons

Ion a atom or group of atoms with an electrical charge

Cation a positively charge ion

Anion a negatively charged ion

Ionic bonding a chemical bonding that involves the electrostatic attraction between apoosedly charged ions

Covalent bonding a chemical bond that involves the sharing of electrons to form elecgtron pairs

Metallic bonding a type of chemical bonding that arises from the electrostatic force

Mineral a naturally occurring substance

Streak

Know moh’s scale including:

Hardest, softest minerals diamond gold talc

Hardness of fingernails, glass,    nail 2.5 glass 5.5

1. How do temperature and pressure change with depth?
Temperature and pressure both increase with depth inside the Earth. Temperature rises at a rate known as the geothermal gradient, which averages about 25–30°C per kilometer of depth in the crust. Pressure increases as you go deeper because of the weight of the overlying material.

2. What are the differences between continental crust and oceanic crust?

• Continental crust is thicker (about 30–50 km) and less dense than oceanic crust. It is composed mostly of granite and is older.

• Oceanic crust is thinner (about 5–10 km) and denser than continental crust, made primarily of basalt, and is generally younger.

3. What is the Moho?
The Moho (Mohorovičić Discontinuity) is the boundary between the Earth's crust and the mantle, where there is a noticeable change in seismic wave velocities.

4. What is the mantle composed of? How thick is it relative to the crust and core?
The mantle is composed of silicate rocks rich in magnesium and iron, such as olivine and pyroxene. It is about 2,900 kilometers thick, much thicker than the crust, and extends from the Moho to the outer core.

5. What is the core composed of? What part is liquid? What part is solid?
The core is composed mainly of iron and nickel. The outer core is liquid, while the inner core is solid. The solid inner core is under immense pressure and remains solid despite high temperatures.

6. Who was Wegener and what did he propose?
Alfred Wegener was a German meteorologist and geophysicist who proposed the theory of continental drift in 1912. He suggested that continents were once joined together in a supercontinent called Pangaea and had since drifted apart.

7. What were the main observations that Wegener made? What was his evidence for plate motion?
Wegener's main observations included:

• Similar rock formations and fossil evidence across continents that are now separated by oceans.

• Geological features like mountain ranges that align across continents.

• Evidence of past climates (e.g., glaciers found in now-tropical regions). His evidence suggested that continents had once been connected and later drifted apart.

8. Why didn’t scientists believe Wegener? What do you think about their alternative ideas?
Scientists didn’t initially accept Wegener’s theory because he couldn’t explain how the continents moved. His proposed mechanisms, like continents "plowing" through the oceanic crust, were unconvincing. Later, the theory of plate tectonics, which provided a more plausible explanation with seafloor spreading and subduction, gained acceptance.

9. What does the ocean floor look like?
The ocean floor has a varied topography, including mid-ocean ridges, deep ocean trenches, abyssal plains, and seamounts. The mid-ocean ridges are volcanic mountain chains where new oceanic crust is formed.

10. What is ocean crust composed of?
Oceanic crust is primarily composed of basalt, a dark, iron- and magnesium-rich rock that is denser than the granite that forms continental crust.

11. With respect to tectonic plates and their boundaries, where do earthquakes occur?
Earthquakes typically occur along plate boundaries, especially at convergent (colliding), divergent (separating), and transform (sliding past each other) boundaries, where stress builds up and is released.

12. What is the difference between convergence and divergence?

• Convergence refers to the movement of two tectonic plates toward each other, leading to subduction or continental collision.

• Divergence refers to the movement of two plates away from each other, often at mid-ocean ridges where new crust is created.

13. What are the three main types of plate boundaries?
The three main types of plate boundaries are:

• Divergent boundaries (plates move apart, e.g., mid-ocean ridges).

• Convergent boundaries (plates move toward each other, e.g., mountain ranges or subduction zones).

• Transform boundaries (plates slide past one another, e.g., the San Andreas Fault).