によって Aishah Aziz 8年前.
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Topic 2: Periodic Table
The periodic table organizes elements based on their properties and recurring trends. Transition metals, found in groups 3 to 12, are known for their high electrical conductivity, malleability, and high melting and boiling points.
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Transition Metals (G3 - G12) Malleable High electrical conductivity High melting & boling point Topic 2: Periodic Table Alkali metals (G1) with oxygen to form oxides e.g. Li2O with water to form hydroxides and hydrogen e.g. KOH with halogens to form halides e.g. NaOH Shiny when freshly cut Easy to cut Noble gases (G18) Colourless Monoatomic Inert (Non- reactive) Halogens (G17) Poor conductors of electricity Exist as diatomic molecules Form halide when react with less electronegative elements HX (aq) + H2O (l) → X- (aq) + H3O+ (aq) Strong smell Reacitivity decreases down the group Alkaline earth metals (G2) Reaction Mg(s) + H2O(g) → MgO(s) + H2(g) 2Mg(s) + O2(g) → 2MgO(s) MCO3(s) → MO(s) + CO2(g) Soft, silver metals Metalloids (G13) Ductile & malleable Semi-conductive Solid at room temperature General Trends Ionization energy Electronegativity Ionic radii Atomic radii
