Enem Sergipe: teacher gives chemistry tips for the second day of exams

In the countdown to the second Sunday of the National High School Exam (Enem) exams, the Conexão Enem panel, shown on SE1, brought important chemistry guidance this Thursday (12). Recorded on the banks of a river, the tip addressed the properties of water and the environmental impacts related to water resources.

During the explanation, the professor highlighted recurring points in the Natural Sciences tests and warned candidates not to confuse different types of water pollution.

Main points of the review class:

Polarity of water: Students must remember that water is a polar molecule, following the principle of solubility in which "like dissolves like".

Eutrophication: It is an environmental problem caused by excess organic matter and nutrients in the water. This accumulation causes the proliferation of bacteria that consume the oxygen dissolved in the environment. When dealing with this topic, the candidate must associate the concepts of Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD).

Eutrophication x Nuclear Power Plant: The professor warned about the difference between the two phenomena. While eutrophication involves biochemical processes, the environmental impact caused by nuclear plants occurs through the heating of water (thermal pollution), which reduces the solubility of gases and causes oxygen to escape from the aquatic environment.