Atmospheric pollutants from fuels 4.9.3.1 Flashcards
What gases are released in the atmosphere when a fuel is burned?
>Carbon dioxide >Water vapour >Carbon monoxide >Sulphur dioxide >Oxides of nitrogen
What is the cause of the pollutant carbon monoxide and how can it be reduced?
> Cause: incomplete combustion
>Reduced: catalytic converter convert to CO2
What is the cause of the pollutant sulphur dioxide and how can it be reduced?
> Cause: burning fuels containing sulphur
>Reduce: removed from power stations by limestone
What is the cause of the pollutant oxides of nitrogen (NOx) and how can it be reduced?
> Cause: from N2 and O2 at very high temperatures
>reduce: converted to N2 by a catalytic converter
What are the problems with bacteria reproducing so quickly?
- food spoilage
- spread of disease
Why did we incubate at 25°C?
Prevent harmful bacteria growing
Why did we store the plates upside down?
Stop condensation falling onto the bacteria
Bacteria are incubated at 25⁰C. the optimum
temperature for their growth is 37⁰C. Discuss why it is important to culture bacteria at temperatures no lower than 25⁰C but also not around 37⁰C.
Temperatures lower than 25⁰C are not warm enough for enzymes to function at optimum rates of reaction are too low for cell division to take place. Temperatures around 37⁰C are too close to human body temperature and could lead to uncontrolled growth rate of bacteria
use of all nutrients in Agar resulting in a dead culture
higher risk of infection/contamination to person carrying out the investigation