Chemistry module 2.4 Flashcards
What are the main pollutants released from a car engine?
Carbon monoxide
Oxides of nitrogen
Unburnt hydrocarbons
How is CO formed and where does it come from?
Formed from the incomplete combustion of hydrocarbons
Traffic pollution
Why is CO harmful to the human body
Can bind to haemoglobin molecules reducing the amount of O2 supplies to tissues and organs
Heart and brain specifically affected and people with cardiovascular disease
What are the symptoms of carbon monoxide poisoning?
Disturbed vision
Fatigue
Reduced movement
Inability to form complex tasks
What are the two oxides of nitrogen and how are they caused?
NO2 and NO
- during fuel burning in internal combustion engine air is drawn into cylinder and burns with O2 for energy
- nitrogen from air oxidised to form to oxides
Why is NO2 harmful?
Why is NO harmful?
- formation of low level ozone and acid rain
- respiratory irritants and low levels affect asthmatics
How are VOCs released and why are they bad
- vehicle exhaust gases from unburnt fuels especially benzene and buta-1,3-diene
- both are human carcinogens
- react with NO2 to form low level ozone which causes breathing difficulties and increased susceptibility to infections
What is a catalytic converter made out of?
Platinum
Rhodium
Palladium on a honeycomb mesh
How does a catalytic converter work?
Hot exhaust gases pass over the catalytic surface and the harmful gases are converted into less harmful gases and released into the atmosphere
Define sustainability
The development of processes that prevent of the depletion of natural resources
WHAT BONDS ARE INFRARED RADIATION ABSORBED BY
C=O
O-H
C-H
WHERE DOES THE EARTH RECEIVE MOST OF ITS ENERGY
elctromagnetic radiation from the sun
WHERE DOES WATER VAPOR COME FROM
evaporation of lakes and oceans
the most abundant green house gas
WHERE DOES CO2 COME FROM
volcanic eruptions
animal respiration
burning or decay of organic matter
WHERE DOES METHANE COME FROM
cow by products
burning of hydrocarbons
rotting organic waste
WHAT ARE CLATHRATES
ice like structures beneath cold northern seas that hold methane bubbles which if released can have a huge impact on the greenhouse effect
WHAT HAPPENS WHEN GASES ABSORB RADIATION
molecule vibrates
vibrating molecule emits some energy in the form of radiation
radiation absorbed by another GHG or the earths surface
WHAT DOES THE GREENHOUSE EFFECT OF A GAS DEPEND UPON
its concentration in the atmosphere and its ability to absorb infrared radiation
WHAT DOES THE ABSORPTION EMISSION PROCESS DO
keep heat close to the earths surface
WHAT ARE THE EFFECTS OF GLOBAL WARMING
melting ice which means higher sea levels
more erratic weather
glacier disappearing in Europe
drought and disease
WHAT DOES THE KYOTO PROTOCOL STATE
in 1997 that 100 countries are going to reduce their greenhouse emissions of 6 gases by 5% by 2012
APART FROM THE KYOTO PROTOCOL WHAT IS A SOLUTION FOR REDUCING GREENHOUSE EMISSIONS
alternative energy such as wind, tidal, solar and nuclear power
DESCRIBE CARBON CAPTURE AND STORAGE
- carbon captured and stored from power stations
- stored underground in porous rock
- decarbonised fuel makes CO2 and H2 and CO2 is then pumped to an oilfield near the ends of its life
- CO2 helps extract the last 30% of oil
HOW IS CO2 STORED AS CARBONATES
-Reacts with metal oxides e.g.
CaO + CO2 –> CaCO3
MgO + CO2 —> MgCO3
