Chemical Monitoring and Management Flashcards
(26 cards)
What is a flame test?
An example of emission spectroscopy. Its use depends on the fact that different atoms emit different wavelengths (and hence colours) of light when heated, which allows use to use the colour produced to analyse substances.
What is the Pb2+ confirmation test?
Add I- ions to form a yellow precipitate.
What is the Cu2+ confirmation test?
Cu(OH)2 precipitate dissolves in concentrated NH3 to form a deep blue solution.
What is the Ba2+ confirmation test?
Add SO42- ions to form a white precipitate.
What is the Fe2+ confirmation test?
Forms a white precipitate with potassium hexacyanoferrate(II)
What is the Fe3+ confirmation test?
Forms a dark blue precipitate with potassium hexacyanoferrate(II)
Pb2+ flame test
Dull blue
Cu2+ flame test
Green
Ba2+ flame test
Yellow-green or Apple-green
Ca2+ flame test
Orange red
What is the PO43- confirmation test?
Forms a yellow precipitate with ammonium molybdate (NH4)2MoO4
What is the CO32- confirmation test?
Effervescene as CO2 in acid – test gas with lime water, forms a white precipitate with BaCl
What is the Cl- confirmation test?
AgCl precipitate dissolves in 10% ammonia solution
What is the SO42- confirmation test?
Forms a white precipitate with PbNO3
What are the consequences of long term overexposure of the Lead ion?
Long term overexposure can cause numerous health problems, including anaemia, nervous system disorders, mental retardation, kidney disease and decreased fertility.
What happens to excess lead in the body?
Excess lead accumulates in the bones and teeth where it replaces the natural calcium after the limited 2mg of lead is excreted a day.
Why does lead levels need to be monitored?
Lead interferes with the action of particular enzymes in the body. It inhibits the synthesis of haemoglobin and interferes with energy production by cellular mitochondria.
What are some uses of Lead?
Lead has been used in paints and pipes. It has been used in petrol to improve engine performance. As well as car batteries, roof flashing, automobile enamel paints and industrial emissions.
What are the main pollutants found in the lower atmosphere?
Carbon monoxide, carbon dioxide, oxides of nitrogen, volatile organic compounds, sulfur dioxide, lead, particulates.
What are the source of carbon monoxide?
Incomplete combustion in motor vehicles, stoves, cigarettes, fires.
What are the sources of carbon dioxide?
Burning fossil fuels, deforestation.
What are the sources of oxides of nitrogen?
High temperature combustion e.g. power stations, motor vehicles.
What are the sources of volatile organic compounds?
Unburnt fuels, solvents and paint.
What are the sources of sulfur dioxide?
Smelting metal sulfide ores, combustion of fossil fuels.
