Then Dimitri Mendeleev and Julius Lothar Meyer published in 1869 and 1870, their periodic tables. T

The baseline chemistry brings a problem for students and teachers: the horrible Periodic Table and its various rules, names and "decorebas". But learning webself about the chemicals have to be like?
The table is a way to classify and compare the different chemical elements. Since 1789 Lavoisier published a list with 33 elements grouped into gases, metals, non-metals and earth, other chemists spent the next century seeking a way to more precise classification. Several of them have identified relationships between small groups of elements, but failed to build a system to organize all the elements described so far.
Then Dimitri Mendeleev and Julius Lothar Meyer published in 1869 and 1870, their periodic tables. They built them similarly: listed the elements in order of atomic webself weight and starting a new line when the characteristics of the elements began to repeat.
The success of Mendeleev's table came from two decisions webself he made: Leave gaps when it seemed that the corresponding element had not been discovered; this was done so precisely that various chemical elements discovered after they had already booked their places in the original table. Ignore the order suggested webself by the atomic weights of some elements to better classify them into chemical families.
In 1923 the physicist Henry Moseley identified some inversions in the correct order of the Periodic Table and corrected a mistake made through lack of knowledge and technology error: webself the elements should be ordered by their atomic number (number of protons in its nucleus), and not by their mass, as was customary.
Thus, the structure of the periodic table demonstrates recurring chemical webself properties (hence the "regular" name), being the elements listed in order of increasing atomic number. Until March 2010, before the 60 elements of the table organized webself by Mendeleev were 118.
In this case there is not much to do. It is very good to know at least the most common elements in exercises and tests (such as H, O, C, Na, Cl, S, P, K, F, etc.). But that does not mean that the teaching and study of chemical elements need be tiring, interesting activities can cause the elements and their properties is learned without decorating the contents of the books!
Long time blog accompany the Periodic Table, maintained by Professor Luis Brudna. There you have access to an interactive table where each element has a special page with their important features.
It turns out that the blog has a much different thing than what you see in books and can be a great tool to study when you start thinking about playing your textbook out the window (or in the teacher's head). webself
The coolest thing you can see are the videos. They contain explanations of each element and interesting chemical reactions. Some of them are a little webself explosive, as the reaction of a handful of metallic sodium (Na) with water shown below!
Study the table is always a challenge. It is difficult to understand periodic properties, aperiodic, as the elements were arranged in the table and how these properties relate to the formation of substances.
Thus, a work published in the February 2010 Journal of Chemistry New School addressed the development and implementation of a game on the Periodic Table and their properties to students in elementary and high school.
The game was developed based on existing commercial game called Super Trunfo letters, and allowed students to treat the theme dynamically. Comparisons between the chemical elements during the game help you understand the positioning of each chemical element in the periodic table possible, easing lasting learning.
The game discussed in the article was developed with 98 chemical elements and worked the following properties: atomic number, atomic weight, boiling point, melting point, density, electronegativity and electronic configuration. Of course this is not mandatory, each can develop his game thinking of the greatest difficulties of their students!
The production webself of the cards is very simple and a tip is to do this in conjunction with students, so that the activity is interesting since its inception. With cardboard, ruler, scissors, pens and a textbook, all cards are prepared and distributed in equal amounts among the participants.
The game is simple: if you are first to act, to choose a letter and say that information wants to confront the cards the opponent. webself For example, boiling point greater or lesser density. When your opponent choose the letter that he put in dispute, you should put the cards on the table and compare values. Who has the highest or lowest value, the board cards wins!
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