Metalele în viața noastră referat
Răspunsuri la întrebare
In the Middle Ages only 7 metals were known: gold, silver, copper, tin, lead, iron and mercury. Gold was considered the most precious. It was later discovered that metals in very small quantities are necessary for all vital forms. They enter the living cell in the form of cations, but their encapsulation is strictly regulated, because in large quantities virtually all metals are toxic. Man, like other vertebrates, needs metal cations, which ensure the development of many vital processes. Metals also play an extremely important role in the economy of any country. The most widespread use is in terms of metal: iron, aluminum, silver, copper and others. Iron has a vital importance, being metallic without which there can be no world around and without which it is impossible in our lives. In the form of ions, it is part of hemoglobin, giving the blood its red color (in the blood of a mature person, more precisely in hemoglobin, there are 3 grams of iron (II)) and ensures the transport of oxygen through the human body. From other beasts, cast iron and steel, ships, railways, aqueducts, tools, the use of factories and factories are built. Aluminum is used in the production of airplanes, electric cables, household items, being called in the twentieth century "winged metal". In chemistry lessons, I propose the primary goal that students, based on the physical and chemical properties studied, to deduce the areas of use of metals and their biological role, their advantages and disadvantages in human life. Even after the color of the ions of some metals, students easily assume their presence and function. For example, calcium is part of the group of vital metals and in the form of compounds is found in bones and teeth, giving them hardness. I create the student's activity and interest in the discipline through didactic play, because it raises any vomit in the soul remains a child.