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Chemistry, pneumonic - Coggle Diagram

- - - - chlorine is gas
      - bromine is a liquid
      - iodine is a solid
    - - outer shell of electrons is farther away
      - force of attraction between nucleus and outer shell deacreases
      - it becomes harder and less likely that the halogen will gain an electron
  - - - cold wool burns to make iron(iii) flouride
    - - hot iron wool burns vigorously to make iron(iii) chloride
    - - hot iron wool burns quickly to make iron(iii) bromide
    - - hot iron wool reacts slowly to create iron(iii) bromide
  - - - explodes with a flame or in sunlight
      - forms hydrogen chloride
    - - vigorous reaction when warmed
      - forms hydrogen bromide
    - - explodes at room temperature, in the dark
      - forms hydrogen flouride
    - - very slow reaction when heated strongly
      - forms hydrogen iodide
  - - - most reactive
        
        flourine
      - least reactive
        
        iodine
      - chlorine
      - bromine
- - - - warm gently with bunsen burner
        
        add copper oxide and stir until it dissolves completely within the acid
        
        keep adding copper oxide until it stops dissolving
        
        filter out the unreacted copper oxide
        
        pour the solution into an evaporating basin and place it on a beaker of water
        
        heat water using a bunsen burner until it boils. The steam will warm the evaporating basin containing the copper sulfate until blue crystals start forming around the edges of the copepr sulfate solution
        
        1 more item...
        
        solution in this case is copper sulfate
  - - - take a jar of chlorine. In a fume cuboard, open the jar.
        
        melt the sodium on a heatproof tile
        
        once molten, place the jar on top of the sodium.
        
        sodium starts to burn and produces white particles
        
        the white particles are sodium chloride
  - - - burette
      - pipette and filler
      - conical flask and white tile
    - - acid of unknown concentration
        
        hydrochloric
        
        sulfuric
        
        nitric
      - sodium hydroxide solution of a known concentration
      - suitable indicator
        
        methyl orange
        
        phenolphthalein
      - use pipette and pipette filler to add 25cm^3 of alkali to clean conical flask
        
        add a few drops of indicator and put flask on white tile
        
        fill burette with acid and note the starting volume
        
        slowly add the acid from the burette to the alkali in the conical flask, swirl to mix
        
        Stop adding when indicator permanently changes colour. Note the final volume
        
        repeat these steps until you get concordant titrates (within 0.1-0.2 cm^3)
- - - - 2H2(g) +O2(g) --> 2H2O2(l)
    - - negative
        
        2H2 + 4OH- --> 4H2O + 4e-
        
        2H2 + 4OH- + O2 + 2H2O + 4e- → 4H2O + 4e- + 4OH-
        
        2H2 + O2 --> 2H2O
      - positive
        
        O2 + 2H2O + 4e- --> 4OH-
    - - 0 tailpipe emissions
      - fast refueling
      - high efficiency
      - sustainable for heavy transport
    - - high cost
      - expensive and sparse refueling structures
      - energy intensive fuel production
      - safety concerns (hydrogen is highly flammable)s
      - storage challenges
  - - - cheaper
      - long shelf life (5-10 years)
      - good performance in low drain devices
      - safe
    - - single use
      - low performance in high drain devices
      - often end up in landfills (enviromental concern
      - gradual voltage decline
  - - - long term cost saving
      - less waste, less resources needed for batteries (enviromental benefits
      - better performance in high drain devices
    - - higher initial cost
      - needs a charger as well
      - self discharges faster
- - - - strong covalent bonds
      - require a lot of energy to break
      - weak intermolecular forces
      - lower melting/boiling point
    - - graphite
        
        conductive
        
        brittle
        
        lubricant
        
        each carbon atom is conencted to 3 others
      - diamond
        
        strong
        
        non-conductive
        
        each carbon atom is connected to 4 others
      - high melting and boiling points
      - conductivity varies
  - - - have high melting/boiling points due to this strong electrostatic attraction
      - hard
      - brittle
      - non-conductive when solid
        
        are conductive when dissolved or molten as it is the ions that carry the charge, so they need to be mobile
  - - - malleable
      - conductive
        
        electrical
        
        thermal
- - - - if placed in an acid, would cause a neutralisation
      - react with water to create an alkali
- - - - SO4
    - - Cl
    - - NO3
    - - CO3
- - - - STEP 1: calculate amount of sodium hydroxide
        
        mol/dm^3 = amount of solute in mol/volume in dm^3
        
        amount of solute in mol = mol/dm^3 * volume in dm^3
        
        0.100 * 0.0250 = 0.00250mol
        
        volume = 25/1000 = 0.0250 dm^3
        
        STEP 2: find the amount of hydrochloric acid in mols
        
        NaOH + HCl --> NaCl + H2O
        
        mole ration = 1:1
        
        0.00250 mol of hydrochloric acid
        
        20cm^3 = 0.0200 dm^3
        
        mol/dm^3 = 0.00250/0.0200 = 0.125mol/dm^3
        
        STEP 3: calculate the concentration of hydrochloric acid in g/dm^3
        
        relative formula mass = 36.5
        
        mass = relative formula mass * amount
        
        36.5 * 0.125 = 4.56g
- - - - CnH2n+2
      - alkenes are more reactive than alkanes
      - saturated
      - can be an alcohol
        
        these can turn into carboxylic acid when oxidised
        
        COOH at the end of the monomer
        
        OH at the end of the the monomer
    - - cool temperatures (at the top)
        
        LPG
        
        petrol
        
        paraffin
      - hot temperatures (at the bottom
        
        diesel
        
        heating oil
        
        heavy fuel oil
        
        resiude
    - - low boiling point
      - volatile
      - flow easily
      - ignite easily
    - - high boiling point
      - not very volatile
      - does not flow easily
      - does not ignite easily
    - - alkenes are more reactive than alkanes
        
        because of the doube bond
      - CnH2n
    - - shake the test tubes
        
        alkene bromine water will change from orange to colourless
        
        alkane bromine water will be unchanged
    - - catalytic cracking
        
        temperatures of 550 degrees
        
        uses silicon oxide and aluminium oxide for catalysts
      - steam cracking
        
        temperature of 800 degrees
        
        no catalysts
    - - ethanol
        
        relatively safe for consumption
        
        used in alcoholic drinks
        
        2 carbon
        
        produced through fermentation
        
        burns in a blue flame
        
        production
        
        fermentation
        
        C6H12O6 --> 2C2H5OH + 2CO2
        
        renewable due to use of yeast
        
        bad as it produces carbon dioxide
        
        cracking crude oil (ethene)
        
        ethene + water --> ethanol
        
        C2H4 + H2O(g) --> C2H5OH
        
        good as it is fast and only produces ethanol
        
        bad as it is not renewable
        
        uses
        
        perfumes
        
        aftershaves
        
        mouthwashes
        
        reacts with sodium to make sodium ethoxide
      - methanol
        
        much more toxic
        
        used in antifreeze and industrial solvent
        
        causes blindness and death
        
        one carbon
        
        produced through synthesis
        
        burns a white/invisible flame
- - - - electronics
      - sunscreen (transparent UV blockers
        
        sunscreen is made with nanoparticulate zinc oxide
        
        if it is made with bulk zinc oxide, then it becomes solid white
      - risks
        
        because of their likelyhood of reactions happening due to their surface area:volume ratio, there is a risk they bond to toxic substances and are breathed in.
        
        if they enter the body, they could catalyse reactions that are harmful
      - medicine
        
        drug delivery
        
        imaging
        
        nanoparticulate silver is used for wound dressing as it kills bacteria
        
        if not disposed of properly, can cause damage to enviroment by killing bacteria
- - - - Nitrogen (N2) from air
      - hydrogen (H2) from natural gas)
        
        N2 + 3H2 <--> 2NH3
        
        the ammonia it produces has many uses
        
        mostly fertiliser
        
        household cleaning
        
        industrial refridgeration
        
        plastics
        
        explosives
        
        pharmaceuticals
        
        synthetic fibres
        
        dyes
      - iron catalyst
      - uses specific conditions
        
        high temperatures (400-500C)
        
        high pressures (150-200 atm)
- - - - Thompsons 'plum pudding' model (1897)
        
        Cathode ray experiment (1909-1911)
        
        aimed beams of positively charged particles at a very thin gold foil
        
        according to the plum pudding model, they should have passed straight through, but many changed directions
        
        atoms have a central, positively charged nucleus
        
        electrons orbit the nucleus like planets around a star
        
        Bohr model (1913
        
        electrons occupy shells or energy levels around the nucleus
        
        atoms have an overall neutral charge
        
        atoms are spheres of positive charge with electrons dotted around
      - atooms cannot be broken down into anything simpler
      - atoms of a given element are identicala
      - atoms of a different element are different
      - during chemical reactions, atoms rearrange to make different substances
- - - - lose electrons
      - gain charge
      - oxidising agents
        
        non-metal or positive ion
        
        Uses
        
        great for killing fungi, bacteria and viruses
        
        cause oxidation
        
        can also be used to break down colour compounds
        
        gains electrons/becomes reduced
        
        halogens are extremely strong oxidising agents
    - - gain electrons
      - reduce charge
      - reducing agent
        
        metal or negative ion
        
        loses/donates an electron to another atom (gets oxidised)
        
        alkali metals are the strongest reducing agents
        
        carbon monoxide is used for metal extraction as a reducing agent
    - - Mg(s) --> Mg2+ + 2e- (oxidation)
        
        Mg(s) + Cu2+(aq) --> Mg2+(aq) + Cu(s)
      - Cu2+(aq) + 2e- --> Cu(s) (reduction)