Download What is the difference between oxidation and hydrolysis? What if

What is the difference between oxidation and hydrolysis?
Oxidation = combining with oxygen (burning, rusting)
Hydrolysis = being broken apart by water (dissolved)
What if there were never any mechanical or chemical
weathering? no sediments, no soil, no sedimentary rock – just igneous and
metamorphic rock.
Where would frost wedging occur?
Where ever the
temperature bounces
back and forth between
freezing and thawing
Where does acid
rain occur?
In the U.S., mostly in the
Ohio River Valley and
eastward.
Isn‟t all rain, “acid rain”?
Pure water is pH 7. Most rain is pH 5.7 because it mixes with CO2 in the air and
forms carbonic acid - H2CO3. Below 5.7 is “acid rain”
What causes mass wasting? What helps?
Gravity, aided by water which reduces the friction between particles
Do certain rocks take longer to erode than others?
Igneous and metamorphic crystals are like a battleship welded together.
Sedimentary rocks would be a battleship glued together. Talcott Mt. was once
covered with sandstone!
Are chemical and mechanical weathering like the physical and
chemical change we studied in Middle School? Exactly!
How can plants grow on bare rock?
The
smallest plants, like lichens, can grow on bare rock.
They dissolve the rock to get minerals, and when they
die they become soil.
How are erosion and plate tectonics related?
Plate tectonics
creates volcanoes and mountains that are exposed to the weather
What sort of climate is „best‟ for mechanical weathering?
Where plants grow (root wedging), or where it is gets both hot and cold (frost
wedging and exfoliation).
What sort of climate is „best‟ for
chemical weathering? Warm and
wet! Warm because molecules move
(and react) faster when it is warm, and
wet because water helps
chemical reactions. NO
chemical weathering here!

How do mechanical and chemical weathering work together?
Mechanical weathering breaks the rock into smaller pieces with more surface for
the chemical weathering to attack.
How can a volcano cause a mudflow?
Sulfur from the volcano chemically eats at the rock and weakens it. Snow
accumulates on the top of the volcano. The volcano erupts, melts the snow and
the water washes away the rock. Lahar.
Río Lagunillas, former location of
Armero, Columbia 1985.
Within four hours of the beginning of
the eruption, lahars had traveled 100
km and left behind a wake of
destruction: more than 23,000 people
killed, about 5,000 injured, and more
than 5,000 homes destroyed along the
Chinchiná, Gualí, and Lagunillas rivers. Hardest hit was the town of Armero at
the mouth of the Río Lagunillas canyon, which was located in the center of this
photograph. Three quarters of its 28,700 inhabitants perished.
Volcanic plugs are formed when lava solidifies in the pipe of an extinct volcano.
Over time, the volcanic cone made up of less resistant rocks wears away, leaving
behind the solidified volcanic plug.
The Devil's Tower in Wyoming, USA is a great example of a volcanic plug.
The Devil's Tower, Wyoming, USA.