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  1. B

    Fertiliser prac urgent help

    None of the compounds listed or any possible combination there of should turn red.
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    sulfate content calculation problem

    m1 = 0.728 g m2 = 0.773 g m3 = 0.722 g m4 = 0.732 g ma = 0.73875 g 0.73875 g * 10 = 7.3875 g 7.3875 g / 50 g * 100 % = 14.775 % --- Adding water to the 50 mL sample does not change the amount of sulfate. An aliquot of one tenth the volume is removed so logically one tenth of the sulfate is...
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    Help please.

    Phosphorous is a non-metal. Elemental metals are anything that exhibit metallic bonding and are elementally pure.
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    Separating gases(chemical earth)

    Say you wanted to liquify nitrogen and oxygen from the air. Dry air is composed of nitrogen, oxygen, argon and carbon dioxide plus traces of other gases. Nitrogen condenses at 77.36 K, oxygen at 90.20 K, argon at 87.30 K and carbon dioxide at 216.6 K. The order of condensation will be carbon...
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    Cyclohexene + Bromine Water

    HOBr is hypobromous acid not bromine hydroxide. The ionisation products are H+ and BrO-. The products of Br2(l) + H2O(l) --> HOBr(aq) + HBr(aq) are both acids.
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    Cyclohexene + Bromine Water

    Br2 + H2O --> BrOH + HBr
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    Do you think it's better to write the risk assessment before or after the method?

    It should be part of the appendix at the end of the report followed by all the data.
  8. B

    iupac, systematic names

    The 1,2- indicates that there is a bromine atom on carbon 1 and one on carbon 2.
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    Assessment Task: The Acidic Environment

    You will need to greatly expand on the dot point answers if the assessment is a report.
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    A question about the effect of no sunlight on cycloalkanes and cycloalkenes

    Br2(l) + H2O(l) --> Br2(aq) Br2(l) + H2O(l) --> HBr(aq) + HOBr(aq)
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    A question about the effect of no sunlight on cycloalkanes and cycloalkenes

    Youve drawn a substitution reaction. Your product is still an alkene. Bromine + alkene is an addition reaction to form an alkane. C6H12 + Br2 --> C6H12Br2 Although technically the reaction is: Br2 + H2O --> HBr + HOBr and both C6H12Br2 and C6H12BrOH are formed.
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    A question about the effect of no sunlight on cycloalkanes and cycloalkenes

    It is coloured. When it reacts with the alkene it forms a colourless product. The change from coloured to colourless indicates that a reaction has occured. Whereas if you were going to add water across the double bond, the mixture would start colourless and remain colourless. You cant be certain...
  13. B

    a few quetsions

    C D A H = m * C * dT H = 100 * 4.18 * 17 H = 7106 kJ.mol-1
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    It will precipitate during flocculation as aluminium phosphate or calcium phosphate depending on the flocculant.
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    free radicals

    No Both of those equations are electrically unbalanced. CFCl3 --> CFCl2. + Cl. CFCl3 --> CFCl2+ + Cl- See the difference? One of the C-Cl bonds has broken. In the first equation the C keeps one electron and the Cl keeps the other electron. They are both radicals. In the second equation the C...
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    free radicals

    The . represents a single electron which is required by a radical. The - represents a pair of electrons which is required by an anion. So yes the . must be displayed.
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    Ethanol as a fuel

    A couple more points for you all Octane is immiscible in water and less dense so in the event of a spill it will form a distinct layer on top of water allowing for easy clean up. Where as ethanol is miscible in water so the result will be a toxic alcohol solution which cannot be cleaned...
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    States of ethanol and glucose in fermentation

    Methane boils at -161.5 oC, ethane at -88.6 oC, and ethene at -103.7 oC. There wont be a time when any of them are liquid.
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    How to round up the numbers in calculation

    Do not ever round off in the middle of a calculation. Give the answer with all of the decimal places and then again to the required number. If the answer is being used in another calculation use all the decimal places from the first answer.
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    Whose screwed for Industrial?

    People say that every year and one year soon theyre going to get bitten on the arse. Learn everything in the syllabus.