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[Chem] carbon compound (perspex question and share)

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carbon compound (perspex question and share)

how to do the following question !!!thx!!!
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iii. To cool down the gas to form liquid monomer.
iv. Fume cupboard.

有錯請指
【DSE Maths】中大教育文憑 × 數學系畢業◆助你奪*升Lv~
首次以課題分班,10月開班招生,快d黎睇下~

導師簡介:按此進入

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回覆 #2 傑Simon 的帖子

i know this two
but how about the other

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i.  A white gas might be observed first then liquid appears.
v. Acidified potassium permanganate solution would be decolourized.

有錯請指
【DSE Maths】中大教育文憑 × 數學系畢業◆助你奪*升Lv~
首次以課題分班,10月開班招生,快d黎睇下~

導師簡介:按此進入

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does anyone know the other questions?

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ii) the solid perspex change to liquid states.
iii) condense the gas monomer to liquid state.
iv) Should carry out in fume-cupboard.
It is because the gas monomer is toxic.
v) the purple liquid change to colourless.
vi) it can save money.

if i have any wrong, please forgive me and tell me.

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Official marking scheme :


(ii) Perspex chips melts to a yellowish liquid, then chars / Vapour / fumes formed above the
    molten Perspex.        ½+½
    (Any 2 observations, ½ mark each.)

(iii) To condense the monomer. / cool down the monomer.   1

(iv) Fume cupboard. / fume chamber / fume hood / hood        1

     Fumes of the monomer may be uncondensed, the vapour is toxic. / hazardous to health.  1

(v) Acidified potassium permanganate solution will be decolourized./KMnO4 solution will change
     from purple to colourless.

(vi) The monomer is expensive / Reduces pollution from discarded polymer        1

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