Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
BTEC 2012 UNIT 2 (CHEMISTRY) ASSIGNMENT 5
Transcript of BTEC 2012 UNIT 2 (CHEMISTRY) ASSIGNMENT 5
volcanoes are formed when magma moves from below the crust.
It then cools and forms new (solid) rock
Volcanoes often form at the boundaries (edges) of tectonic plates
Volcanoes often erupt with little warning.
An eruption is often caused when the pressure of gases dissolved in the magma build up until the crust can't hold it can the magma explodes
These eruptions are often caused by the movement of tectonic plates
when an eruption occurs huge amounts of lava, ash, smoke & gases are released Mining Metal Extraction Positive effects of mining
Valuable metals are produced these have
many important uses in society
Mining provides lots of jobs in the local community Negative effects of mining
The solid waste from mining can contain poisonous heavy metals like mercury and lead
Heavy metals can pollute the land and poison animals and plants
Heavy metals can leach in water supplies for animals and humans, poisoning people
Heavy metals can build up in the food chain and damage health of a wide range of organisms
Large mines are basically large holes in the ground, they can destroy animals habitats and look ugly
Metal mines produce lots of waste rock which has to be disposed of or stored
Mining produces lots of dust which can cause breathing problems ( it can also cover plants and stop them photosynthesisng)
Noise pollution from blasting Mining is the digging up of rock which contain metals.
These rocks are called metal ores
Mining for other materials (coal, oil, gas, minerals, diamonds etc with similar problems & consequences) obviously occurs but we will focus on metals Fossil fuels are burned to produce the energy to extract the metals from the ore, this produces Carbon dioxide and sulfer dioxide
Metals are usually extracted from their ores using carbon, this produces carbon dioxide
sulfer impurities in the ore often reacts to form sulfer dioxide
Carbon dioxide is a greenhouse gas this leads to global warming and possibly changing climate
Sulfer dioxide produced dissolves in rain to form acid rain which can damage plants and marine animals What are the problems?
Sulfer dioxide dissolves in rain water to cause acid rain
Carbon dioxide is a greenhouse gas
What do greenhouse gases do?
They absorb Infra Red radiation, this heat energy is trapped and warms up the Earth's atmosphere. Scientists think this is causing global warming and climate change
Effects of Global warming
1.Spread of disease
As northern countries warm, disease carrying insects migrate north, bringing disease with them.
2. Warmer waters and more hurricanes
As the temperature of oceans rises, so will the number of more frequent and stronger hurricanes
3. Increased probability and intensity of droughts and heat waves
Although some areas of Earth will become wetter due to global warming, other areas will suffer serious droughts and heat waves. Africa will receive the worst of it, with more severe droughts also expected in Europe.
4.Polar ice caps melting
First, it will raise sea levels.
Second, melting ice caps will throw the global ecosystem out of balance.
Third, temperature rises and changing landscapes in the Artic Circle will endanger several species of animals.
Fourth, global warming could snowball with the ice caps gone. Ice caps are white, and reflect sunlight, much of which is reflected back into space, further cooling Earth. If the ice caps melt, the only reflector is the ocean. Darker colors absorb sunlight, further warming the Earth.
5. More floods
the sea’s surface level increase many low-lying or coastal communities and facilities will be under threat of eradication should the sea levels continue to rise. An increase of just a single meter (3 ft) would submerge considerable sections of the U.S. eastern seaboard, while one sixth of Bangladesh could be lost permanently by a rise of 1.5 m (5 ft), to name just two examples. Effects of acid rain
Damage plants & soils as some plants don't 'like' acid conditions
Damage water ecosystems making them too acidic for life
Damges building (made from carbonate rock (like limestone)) short clip (2 mins) long clip ( 8 mins) http://www.metoffice.gov.uk/climate-change/guide/what-is-it/why/volcano The Earth's crust is split into chunks known as tectonic plates
The plate move around the Earth's surface very slowly ( about 2cm a year, that's about as fast as your fingernails grow)
The movement is caused by convection currents in the mantle underneath dragging the plates along ( these convection currents are caused by heating from nuclear decay in the Earth's core)
The plates can move away from each other, move towards each other or move towards each other
The plates don't move smoothly, they grind against each other until the force is to much and the plates jolt. This is an Earthquake Short term effects of Earthquakes
underwater Earthquakes can cause tsunamis which can be very destructive
destroy building, roads & rail links
cause volcanoes to erupt
rupture gas lines causing explosions and fires Long term effects of Earthquakes/ Plate Movements
Formation of mountain ranges ( Himalayas & Andes)
Continents will move and change shape (so will the oceans)
Change shape of the coastlines of continents something in between? (5 mins) Effects of volcanoes
Lava & Ash contains lots of minerals which enrich soil around the volcanoes, this makes it very good for growing crops
Lava is (very,very) hot, it destroys and burns nearly everything in its path (building, homes, people, plant & animals)
Sulfer dioxide & Ash released into the upper atmosphere can reflect sunlight which can lead to cooling of the Earth
Carbon Dioxide released can add to global warming
Ash clouds can cause breathing difficulties & disrupt air travel
Underwater volcanoes can form new islands as the lava cools (Iceland & Hawaii are volcanic islands)
Volcanoes can form mountain ranges for example the Andes long term effects of Volcanoes
The Early atmosphere was created by volcanoes erupting ammonia, carbon dioxide and methane gases
These gases were converted (through bacteria & the carbon cycle) over millions of year to form the atmosphere that we have today
The carbon dioxide produced had a huge impact on the climate & environment Man vs Volcano!
Both produce carbon dioxide & sulfer dioxide ( which as we know isn't good!)
Human produce much, much more of both gases than all the volcanoes put together Humans can reduce the effects of mining & the gases that are produced by:
using less metals (using other things to build stuff)
using plants & bacteria to extract the metals rather than carbon and/or lots of energy
going back to old mines and using new technology to extract more metals
using different fuels to produce energy Carbon capture
this process is being investigated so carbon dioxide produced from energy or metal production is captured so can't add to global warming Sulphur dioxide can be removed from waste gases after combustion of fuels or extraction of metals.
The sulphur dioxide is treated with powdered limestone to form calcium sulphate. This can be used to make plasterboard for lining interior walls, so turning a harmful product into a useful one.
The sulphur dioxide is treated with powdered limestone to form calcium sulphate
This is called SCRUBBING