The 4 major spheres

Chapter 1; Lesson 1 The Earth System [pages 2-9]
System: A group of parts that work together as a whole. The Earth system is all of the
Earth’s parts working together to create our planet.
Energy: Part of the Earth system. Energy is the ability to do work.
The 4 major spheres: hydrosphere, geosphere, atmosphere, biosphere
Hydrosphere: This sphere contains all of the Earth’s water. Oceans, streams, rivers,
lakes and water vapor are all examples of the hydrosphere.
Geosphere: This is the Earth’s sphere that contains all of the Earth’s rock and metals.
The geosphere goes all the way to the center of the Earth.
Atmosphere: This is the sphere of gases that surround the Earth. The atmosphere
contains such gases as oxygen, nitrogen, water vapor and carbon dioxide.
Biosphere: All of the Life on Earth. The biosphere overlaps all of the other spheres. It is
in the atmosphere, hydrosphere, and geosphere because life is found in all of these
Constructive forces: Forces that build landforms. These include tectonic plate
movement that builds mountains. Earthquakes result from plate movement so they are
constructive forces.
Destructive Forces: These are forces that tear down landforms. Erosion from wind and
water is a destructive force.
1. Oxygen is the most abundant element on Earth. Oxygen combines with other
elements, especially silicon, to form rocks. Silicon is the second most abundant
2. Nitrogen is the most abundant gas in the atmosphere. [78%]
3. Oxygen is the gas in the atmosphere that animals need to breathe. [21%]
4. Carbon dioxide is a greenhouse gas. It holds heat in so it can’t escape into space.
Chapter 1; Lesson 2 Earth’s Interior [pages 10-17]
Two ways scientists study the inside of the Earth:
1] indirect evidence [seismic waves from Earthquakes]
2] direct evidence [rock samples from volcanoes]
Scientists study how seismic waves travel through the Earth to determine how the Earth
is made. The speed they travel and the paths they take give scientists clues.
The 4 main layers of the Earth:
1] inner core 2] outer core
3] mantle
4] crust
1] Inner core: highest pressure and highest heat. It is a solid because the pressure is so
great that liquids cannot form. The inner core is in the center of the Earth. It is made of
iron and nickel and iron.
2] Outer Core: high pressure but not as high as inner core. Very hot, but not as hot as
the inner core. It is a liquid because rock melts at high temperatures but the pressure is
not great enough to keep it from becoming solid. It is made of the metals iron and
3] Mantle: The mantle is a solid, but it is hot and has some movement. There are
pockets of molten rock in the mantle, but it is mostly solid. The mantle is the layer under
the crust. There is a lot of pressure, but not as much as the inner or outer core.
4] The Crust: The outside most layer of the Earth. It is cooler than the other layers. All of
life is found on or in the crust. [and the atmosphere] The crust is a solid.
A] Continental Crust: The crust that is under the landmasses or continents. The
continental crust is the thickest kind of crust. It is made mostly of granite.
B] Oceanic Crust: The crust that is under the oceans. It is thinner than the
continental crust. It is made mostly of basalt.
Lithosphere: The uppermost part of the mantle and the lower part of the crust. This
layer is hard and rigid. The lithosphere is about 40 miles thick.
Asthenosphere: The layer beneath the lithosphere. It is hotter and under more
pressure. It can bend like a spoon without breaking.
Basalt: The rock that makes up the oceanic crust. Basalt is dark and fine grained. It is
made of mostly oxygen and silicon.
Granite: The rock that makes up the continental crust. Granite is light colored and
coarse grained. It is made of mostly oxygen and silicon.
1] The Earth’s crust is made of 46% oxygen
2] The Earth’s crust is made of 28% silicon
3] The Earth’s crust is made of 8% aluminum
4] The Earth’s crust is made of 5% iron
5] The Earth’s crust is made of 4% calcium
Chapter 1; Lesson 3 Convection and the Mantle
[pages 18-21]
There are 3 ways that heat can be transferred.
1] Radiation: Transfer of heat through rays like light.
2] Conduction: Heat that transfers through materials that are touching.
3] Convection: Heat transfer by the movement of a fluid. [air or liquid]
Convection Currents: Currents that move in a fluid that transfers heat. Hotter materials
move upward because they are less dense. When they lose heat and get cooler they get
more dense and sink to the bottom. Then they get hot and move upward again. This
cycle continues over and over moving the material to the top and down to the bottom
Density: How heavy something is compared to its volume. Density is always written as a
ratio between volume and weight [or mass]
Density of Carbon is 2.3g per cm3
The density of lead is 11.3g per cm3
This means that one cubic centimeter of carbon weighs 2.3 grams, but the same size
piece of lead weighs 11.3 grams which is more than 4 times as much. Lead is much more
dense than carbon.
Heat from the core and the mantle cause convection currents in the mantle. This is what
drives plate tectonics. Plumes of mantle rock rise and fall in the mantle like lava in a
lava lamp.
Convection currents occur both in the outer core and in the mantle. The convection
currents in the outer core cause the Earth’s magnetism.
Chemistry Unit:
Chemistry: The study of how matter interacts and how elements and compounds
combine with other elements and compounds to make new materials.
Atom: the smallest particle that has all the properties of an element.
Element: A material that is made of only one type of atom.
Compound: A material that is made of more than one type of atom. [The atoms are
formed into molecules]
Nucleus: The center part of the atom. The nucleus is made up of protons and neutrons,
usually in equal numbers.
Proton: A positively charged particle in the nucleus of an atom
Neutron: A neutral particle in the nucleus of an atom. This means that neutrons do not
have an electrical charge.
Electron: Negatively charged particles that circle around the atom. Electrons are much
smaller than protons and neutrons. They are arranged in shells.
Valence Electrons: The electrons in the outermost shell of the atom. Valence electrons
are the only electrons to interact with electrons in other atoms. They combine with
other electrons to form compounds.
Periodic Table of Elements: A table that shows the basic characteristics of all of the
elements. They are arranged into different categories, and from least number of
protons to most protons.
Nobel Gases: These are gasses that do not combine with other elements, so they are
not found in compounds.
Atomic Number: The number of protons in the nucleus of an atom for each element.
For example, oxygen is atomic number 8 because there are 8 protons in the nucleus.