Cambridge IGCS Chemistry Coursebook 2023 Chapter 13 知识点整理

这是一篇关于The periodic Table的思维导图，主要内容包括：Trends across a period，Trends in groups，Classifying the elements。

The periodic Table

• Classifying the elements
  • Groups and the Periodic Table
    • Periodic Table: A table of elements arranged in oder of increasing proton number to show the similarities of the chemical elements with related elctronic configurations
    • Groups: Vertical columns of the Periodic Table containing elements with similar chemical properties; atons of elemtns in the same group have the smae number of electrons in their outer energy levels.
    • Period: A horizontal row of the Periodic Table
    • Metals and non-metals
      • Metalloids: Such elements have some of the properites of metals and the others that are more characteristic of non-metals.
      • Main-group elements: The elements present in Group I to VIII of the Periodic Table.
      • Transition elements: Elements from the central region of the Periodic Table-they are hard, strong, dense mentals, which form compounds that are often coloured
      • Alkali metals: The Group I
      • Halogens: The Group VII
    • Position of hydrogen in the Periodic Table
      • Hydrogen doesn't belong to any group
  • Organisation of the Periodic Table
    • Periodic property: a property of the elements that shows a repeating pattern when plotted against proton number
      • Elements in the same group have the same number of electrons in their outer shell.
      • Numbers of Periods of the Periodic show us how many shells of elctrons the atom has.
    • Noble gases: Elements in Group VIII - a group of stable, very unreactive gases
    • Relationship betweem group number and ionic charge
      • ↓ metal getting more reactive, densities and melting points increase, atoms getting larger, more metallic → atoms getting smaller, less metallic ↑ non-metals getting more reactive
• Trends in groups
  • Group I - the alkali metals
    • The melting and boiling points become lower
    • Metals get softer
    • Densities increase (not exactly)
    • Chemical reactivity increase
  • Group VII - the halogens
    • halides: compounds formed between an element and a halogen
    • Poisonous and have similar strong smell
    • Nom-metals
    • Form diatomic molecules
    • Have a valency of 1
    • Compounds with hydrogen are strong acids
    • Chemical reactivity of the halogens
      • Halogen displacement reactions: Reactions in which a more reactive halogen displaces a less reactive halogen from a solution of its salt.
  • Group VIII - the noble gases
    • The electron electronic configurations are energetically readily with other atoms
    • Do not react readily with other
    • Atoms of other elements bound or react chemically are trying to achieve the energetically stable arrangement of electrons.
• Trends across a period
  • Changes across a period
    • →↑ atomic size decreasing
  • Transition elements
    • Hard and strong
    • High density
    • High melting and boiling points
    • many of their compounds are coloured
    • often act as catalysts
    • often show more than one valency (variable oxidation number)
      • Oxidation number: a number given to show whether an element has been oxidised or reduced
    • often form more than one type of oxide
      • The oxides of the lower oxidation state are basic ionic oxides
      • The oxides of the highest oxidation states tend to be covalent and produce acidic solutions in water