The periodic table is a tabular display of the chemical elements, organised on the basis of their properties. Elements are presented in increasing atomic number. The main bod...展开

The periodic table is a tabular display of the chemical elements, organised on the basis of their properties. Elements are presented in increasing atomic number. The main body of the table is a 18 × 7 grid, with gaps included in to keep elements with similar properties together, such as the halogens…收起

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