Topic 1 Flashcards
Greenhouse gas natural sources
CO2: Ocean-atmosphere exchange, Plant and animal respiration. Respiration of soil microbes and aerobic decay of organic matter in soils. Volcanic eruptions.
Methane: Methane-producing microbes in wetlands. Methane producing microbes in termites. Methane producing microbes in oceans.
Nitrous oxide-producing microbes in soil
Nitrous oxide-producing microbes in oceans
Chemical reactions in the atmosphere.
Anthropogenic greenhouse gases and their sources.
Carbon dioxide: Combustion of fossil fuels for electrical energy production and transportation. Cement production and industry. Deforestation.
Methane: Fossil fuel production, distribution and use. Methane-producing microbes in livestock. Landfill and waste.
Nitrous oxide. Agriculture. Combustion of fossil fuels. Nitrous oxide-producing microbes in sewage.
What can influence natural climate change
Variation in solar radiation.
Variation in angular position of the Earth relative to the sun.
Changes in volcanic activity.
Changes in concentration of greenhouse gas in the atmosphere.
What is a primary and secondary pollutant
Emitted directly into the troposphere from a source such as a vehicle exhaust or an industrial plant. (NOx)
Secondary: Products of chemical reactions involving primary pollutants in the troposphere. Ozone (O3)
Why is pipette and burette rinsed with distilled water than analyte solution
To remove reagents from previous use
To remove distilled water from the pipette.
What does a pH indicator do with regards to end-point?
A pH indicator is used to approximate the equivalence point of the titration involving the neutralisation of an acid using a base. The point at which the indicator shows a permanent colour change is called the end-point.
What does a colour change do with regards to end-point?
Colour change a colour change (end-point) occurs after the equivalence point has been reached without the addition of an indicator in some reactions. Redox reactions often involve a colour change as the oxidation number of the titrant and analyte change at the equivalence point, often producing different coloured products.
Gas Chromatography.
Injection port: Sample mixture is injected into the gas chromatograph using a syringe.
Column oven: The column oven heats the sample such the components of the mixture remain in the gas phase inside the column.
Column: The column is long, thin, and contains solid particles that interact with the components of the mixture passing through the column.
Inert carrier gas: An unreactive gas such as helium or nitrogen is used to force the mixture through the column towards the detector. (mobile phase.)
Detector: Records each component as it exits the column. Produces an electronic signal that is sent to the data processor.
Data processor: Used to register, store, display and analyse the data.
Harmful effects of NOx
Nitrogen oxide pollution is associated with damage to the health of animals and plants. Breathing high concentrations of nitrogen dioxide causes inflammation of the lungs leading to reduced immunity and subsequently lung infections such as cold, influenza, and bronchitis.
Also acidic rain hydronium increase depletes soil nutrient in ion exchange
Harmful effects of ozone
Irritates the nose, airway and lungs upon inhalation causing respiratory problems. Also damages plants leading to reduced yield. Ozone is a strong oxidising agent which reacts with and damages many essential molecules in the leaves of plants causing pigmentation (chloris) and necrosis (premature death of cells).
What are catalytic convertors made from
Platinum, Rhodium or Palladium
With regards to the graduation line and meniscus how is the volumes read
The plat of the meniscus on the graduation line.
Examples of calcifying organisms
Shell fish and corals
Atomic absorption spectrometer labelled diagram.
Light source - Emits wavelengths that are absorbed by electrons of the atoms of the element under analysis
Flame - High temperature flame used to vaporise sample.
Monochromator - isolates wavelength of light from the light source and allows this wavelength to be transmitted to the detector under analysis.
Detector - Converts the transmitted light into an electric current.
Data processor. Used to register, store, display and analyse the data.
