The Periodic Table: Chemistry Revision - PDF

Here is the conversion of the images into structured markdown format: ## Page 1 ### 4 The Periodic Table The **Periodic Table** is a classification of all the elements based on **atomic number**. The modern table is composed of horizontal **periods** and vertical **groups** which contain the elem...

Here is the conversion of the images into structured markdown format: ## Page 1 ### 4 The Periodic Table The **Periodic Table** is a classification of all the elements based on **atomic number**. The modern table is composed of horizontal **periods** and vertical **groups** which contain the elements arranged: * in order of increasing atomic number * in relation to the electron structure of their atoms * in relation to their chemical properties. **PERIODS** These are horizontal rows of elements. There are **seven** periods numbered 1 to 7: * Elements of one period all have the same number of electron shells. * Going across a period, each element has one more proton and one more electron than the previous element. * Going across a period, the chemical properties of elements become less metallic and more non-metallic. **GROUPS** These are vertical columns of elements. There are eight groups numbered I to VII with a final group 0: * Each element in a group has the same number of electrons in its outer shell for elements in Groups I to VII, this number is the same as the group number. * The common oxidation state (number) of elements in Groups I to IV, when present in compounds, is the same as the group number. The common oxidation state of elements in Groups V to VII, when present in compounds, is the group number minus 8 (see pp. 62-3). Oxidation state is a measure of the electron control that an atom has when present in a compound, compared to the atom in the pure element. * Going down a group, each element has one more electron shell than the previous element. * Elements in the same group have similar chemical properties. * The metallic nature of elements increases down a group. * The reactivity of metals increases down a group. * The reactivity of non-metals increases up a group. Between Groups II and III are the transition metals. All have two electrons in their outer shell and most exhibit variable oxidation states when in compounds. ## Page 2 The image is a diagram of "The Periodic Table in outline". * A vertical arrow indicates metallic nature increases down, in periods 2, 3, 4, 5, 6, and 7. * Francium (Fr) indicates 'Most reactive metal'. * A horizontal arrow indicates transition metals. * A large vertical arrow indicates metallic nature increases. * A key shows "= Metals" and "= Non-metals". * Horizontal arrows indicate "Most reactive non-metal, fluorine (F)". Groups III, IV, V, VI, VII shown on the diagram. ## Page 3 ### Table 4.1 Trends in Group II - the alkaline earth metals | Element | Melting point | Ease of ionisation | Strength as a reducing agent | Reactivity with oxygen, water, dilute $HCl(aq)$ and dilute $H_2SO_4(aq)$ | Displacement | Stability of compounds | Solubility of strength of oxides | Solubility of hydroxides | Solubility of carbonates/sulphates | | -------- | ------------- | ------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------- | ------------------------------------------------------ | ----------------------- | ---------------------------------- | ------------------------- | ------------------------------------ | | Be | | | | | | | | | | | Mg | | | | | | | | | | | Ca | (except Mg) | As diameter of atom increases, the more easily it loses valency electrons (see p. 20) to form ions | The more readily an element ionises, the more readily it gives electrons to other elements | Due to increase in ease of ionisation | An element is displaced from its compounds by an element below it in the group | | | | | | Sr | | | | | | | | | | | Ba | | | | | | | | | | NB Arrows show increase in properties. ### Table 4.2 Trends in Group VII - the halogens | Element | Physical properties | MP/BP | Density | Ease of ionisation | Strength as an oxidising agent | Reactivity | Displacement | | ------- | ------------------------------------ | ------- | ------- | ----------------------------------------------------- | ------------------------------- | -------------------------------------------- | --------------------------------------------------------------------------------------------- | | F | Appearance and state at room temperature | | | | Increases | | | | Cl | Pale yellow gas | | | | The more readily an element ionises, the more readily it removes electrons from other elements | Due to increase in ease of ionisation | An element is displaced from its compounds by an element above it in the group | | Br | Yellow-green gas | | | As diameter of atom decreases, the more easily it gains electrons to form ions | | | | | I | Red-brown liquid | | | | | Due to increase in ease of ionisation | | NB Arrows show increase in propeties. ## Page 4 ### Table 4.3 Trends in Period 3 | Element | Na | Mg | Al | Si | P | S | Cl | Ar | | ---------------------- | --------------- | --------------- | --------------- | -------- | ------------------- | ----------- | ----------- | --------------- | | Metallic nature | | | | | | | | | | Non-metallic nature | | | | | | | | | | Electrical conductivity| | Good conductors | | Semi-conductor | | Non-conductors | | | | Ease of ionisation | As number of valency electrons (see p. 20) decreases, the fewer electrons the atom has to lose to form a cation | | | As number of valency electrons increases, the fewer electrons the atom has to gain to form an anion | | | |Does not ionise| | Reactivity | | | | | Does not decrease ises| Unreactive | | Unreactive | | Reducing/oxidising properties | | Strength as a reducing agent | | | Strength as an oxidising agent | | Formula of oxide | $Na_2O$ | $MgO$ | $Al_2O_3$ | $SiO_2$ | $P_4O_6$ $P_4O_{10}$ | $SO_2$ $SO_3$ | | None | | Bonding/structure of oxide | Giant ionic lattice| Giant ionic lattice| ionic with some covalent character | giant atomic lattice | | Nature of oxide| Basic| Basic| Amphoteric| Acidic| | | Formula of chloride | $NaCl$ | $MgCl_2$ |$AlCl_3$ | $SiCl_4$ | $PCl_3 \ PCl_5$ | $\cdot$ $\cdot$ | $|Cl_2$ | None. | | Bonding/structure of chloride| lonic with high covalent character |lonic with high covalent character| Giant ionic lattice| Covalent molecules| |Covelent | |Bonding structure is ionic| | Amphoteric| |