3 interactive labs · O Level Chemistry 5070
· Build a water treatment plant stage by stage until river water is safe to drink, then test samples for water and for purity.
Build a water treatment plant stage by stage until river water is safe to drink, then test samples for water and for purity.
You will be able to
· Run a city's traffic, power station and farms, watch six pollutants and the acidity of the rain, then cut them with catalytic converters and desulfurisation.
Run a city's traffic, power station and farms, watch six pollutants and the acidity of the rain, then cut them with catalytic converters and desulfurisation.
You will be able to
· Watch sunlight and infrared radiation pass through the atmosphere, add greenhouse gases, then run the carbon cycle and try to stop carbon dioxide rising.
Watch sunlight and infrared radiation pass through the atmosphere, add greenhouse gases, then run the carbon cycle and try to stop carbon dioxide rising.
You will be able to
Examiner's note. Match each pollutant to its source precisely: carbon monoxide and particulates come from incomplete combustion of carbon-containing fuels, oxides of nitrogen from the reaction of nitrogen and oxygen in car engines, and sulfur dioxide from burning fossil fuels that contain sulfur compounds. A common error is to blame carbon dioxide for acid rain; acid rain comes from SO2 and oxides of nitrogen. For catalytic converters give the equation 2CO + 2NO → 2CO2 + N2.
Examiner's note. Name the radiation correctly: greenhouse gases let short-wave (visible) radiation through, but absorb the infrared (thermal) radiation emitted by the Earth's surface and re-emit it in all directions, including back towards the Earth. A common error is to say the gases trap the Sun's rays or that the ozone hole causes global warming. In the carbon cycle, photosynthesis is the process that removes carbon dioxide from the atmosphere.
