Chemistry inorganic

HideShow resource information
  • Created by: rach555
  • Created on: 21-05-18 12:23
View mindmap
  • Inorganic
    • Group 2
      • Atomic radius
        • Atomic radii increase going down
        • Each element has an extra filled main level of electrons
      • Melting points
        • Going down, electrons in 'sea' are further away from positive nuclei
        • Strength of metallic bond decreases
        • Melting point decreases down group
      • Ionisation energy
        • Lose 2 electrons
        • Both ionisation energies decrease down group
        • More electron shells means more shielding so easier to remove electrons
        • Less attraction, easy to remove
      • Reaction with water
        • Metals get more reactive going down
        • Redox reactions
        • In cold water magnesium reacts slowly
        • In steam magnesium reacts rapidly to form an alkaline oxide and hydrogen
        • Basic reaction forms an alkaline hydroxide and hydrogen
      • Extraction of titanium
        • Most metals extracted by reacting metal oxide with carbon to form metal and CO2
        • But doesn't work for titanium
        • So titanium oxide reacts with chlorine and carbon to form titanium chloride, TiCl4 and CO2
        • Then TiCl4 is reduced to titanium by reacting with magnesium
      • Solubility
        • Hydroxides
          • Going down group, they become more soluble
          • E.G Mg(OH)2 is almost insoluble but Ba(OH)2 dissolves
        • Sulfates
          • Going own group, they become less soluble
          • Barium sulfate (BaSO4) is basically insoluble so can be taken as a barium meal to outline gut in medical X-rays
          • Sulfate ion test
            • Sulfate ion solution is acidified with nitric or hydrochloric acid (removes carbonate ions).
            • Then barium chloride is added and white precipitate of barium sulate forms
            • Barium carbonate is also a white insoluble sold so confused with barium sulfate
      • Flue gases
        • React an alkali, CaO or CaO3 slurry with flue gases
        • Called wet scrubbing. Removes SO2
      • Group 2 neutralise acids- Ca(OH)2 neutralises acidic soils. Mg(OH)2 neutralises stomach acid
    • Group 7
      • Electronegati-vity
        • Bond gets further away as atoms get larger down group
        • Increases electron shielding
        • Electronegati-vity decreases down group
      • Physical properties
        • Fluorine is a pale yellow gas, chlorine is a green gas
        • Bromine is a red-brown liquid, iodine is a black solid
        • Atomic radius increases down group as another shell as going down
      • Melting and boiling points
        • Increases down group
        • Larger atoms have more electrons so van der Waals forces stronger
      • Oxidising ability
        • Halogens are oxidising agents so are reduced (gain an electron)
        • Decreases going down group
        • Displacement reactions
          • Halogens react with metal halides
          • in a way that the halide will be displaced by a more reactive halogen not a less reactive one
          • E.G chlorine will displace bromide ions
          • Use ionic equations. any non group 7 element is a spectator ion
      • Reducing ability
        • Larger ions lose electrons easier, so reducing power increases down group
        • Halide ions act as reducing agents
        • Solid sodium halides react with concentrated sulphuric acid
          • Sodium chloride
            • Steamy fumes of hydrogen chloride released. Solid product is sodium hydrogensulfate
            • Not a redox reaction, as chloride ion is too weak a reducing agent
            • Acid based reaction
          • Sodium bromide
            • Steamy fumes of hydrogen  bromide and brown fumes of bromine. Colourless sulphur dioxide formed
            • First reaction is acid based and produces NaSO4 and HBr
            • In second reaction, bromide ions are strong reducing agents to reduce sulphuric acid to sulphur dioxide.
            • In second reaction, the bromine is formed and water
          • Sodium iodide
            • Steamy fumes of hydrogen iodide, black solid of iodine, and hydrogen sulphide gas.
            • Yellow solid sulfur may be seen. And colourless sulfur dioxide
            • First reaction is acid based
            • Second reaction is redox. Iodide ions are best reducing agents
      • Uses of chlorine
        • Swimming pools and drinking water
          • Chlorine reacts with water to form HClO and HCl
          • One chlorine atom increases oxidation   state and the other decreases- called disproportion
          • Chloric acid is an oxidising agent and kills bacteria
        • Chlorine reacts with cold, dilute sodium hydroxide to form sodium chlorate, is a disproportion reaction. Used in bleach
      • Identify metal halides with silver ions
        • All metal halides (not fluoride) react with silver ions in aqueous solution
        • Solution is acidified by dilute nitric acid to remove other ions
          • F- no precipitate, Cl- has white precipitate, Br- has pale very cream precipitate, I- has very pale yellow precipitate
        • Ammonia solution added to precipitates
          • Silver chloride dissolves in dilute ammonia
          • Silver bromide dissolves in concentrated ammonia
          • Silver iodide insoluble in ammonia
    • Period 3
      • Melting and boiling points
        • 1.Sodium to aluminium
          • Strength of metallic bond increases
          • Charge on ion increases so more electrons join delocalised sea
          • Increase melting and boiling points
        • 2.Silicon
          • Giant covalent (macromolec-ular)
          • Increase melting and boiling point
        • 3.Phosphorus to chlorine
          • Molecular so depends on size of Van der Waals forces
          • More electron means greater attration
          • Melting/boiling point= S8>P4>CL2
      • Atomic radii
        • Adding protons to nucleus and electrons to shell
        • Increased charge pulls electron closer to nucleus
        • Stronger nuclear attraction
        • Size of atom decreases
      • Ionisation energy
        • Increases across period
        • Number of protons increase and electrons enter same level
        • Increased charge makes it difficult to remove electrons
        • 1.Magnesium to aluminium
          • Mg loses a 3s electron
          • Al loses a 3p electron
          • P-electron is a higher energy level. So less energy to remove
        • 2.Phosphorus to sulfur
          • P has no paired electron in a p orbital
          • S has two p electrons paired in a p-orbital so easier to remove due to repulsion

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Inorganic resources »