HSC_Chem_Past_Paper_Sol

# 1600 right 1367math mathx 0676 gmath question

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Unformatted text preview: ight ) \times \left ( 12.01 \times 2 + 1.008 \times 6 + 16.00 \right )}{1367}&lt;/math&gt; &lt;math&gt;x = 0.676 g&lt;/math&gt; Question 18: Key Points: Biopol. Impacts on ''Environment'' because: *100% Biodegradable *Renewable Resource Impacts on ''Society'' because: *Biocompatable - Used in stuches and other things that are artificially put inside the human body. As it is biocompatable the body will not reject it. Question 19: Cell X (a) Cannot be recycled or recharged therefore contributes to landfill. :&quot;Candidates are reminded that their answer should identify a specific impact rather than offer a general statement, such as the chemicals harm the environment.&quot;&lt;sup&gt;1&lt;/sup&gt; (b) :&quot;Better responses included balanced half equations or an overall equation and included identification of the anode, cathode and electrolyte.&quot;&lt;sup&gt;1&lt;/sup&gt; Cell Y (a) (b) Question 20: Glucose is fermented to produce a mixture containing ethanol. Fermentation, &lt;!-- REACTION _____________________________________________________________________________________________________ HSC CHEMISTRY PAST PAPER SOLUTIONS – ANDREW HARVEY 9 2000 HSC –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– , is preformed in the presence of a catalyst yeast, warm temperatures (approx 35ºC) and in the presence of CO&lt;sub&gt;2 (g)&lt;/sub&gt;. Over several days a mixture with ethanol in it forms. This mixture is fractionally distilled to extract the ethanol (as ethanol has a low boiling point). This gets pure ethanol which is used to produced ethyl butanoate in a process of esterfication. In esterfication, ethanol, concentrated sulfuric acid (used as a dehydrating agent) and butanoic acid is added to a flask which is heated. This mixture reacts forming ethyl butanoate. Refluxing is used in this process to prevent these volatile substances evaporating. (this solution needs another equation and 2 diagrams for a chance of full marks) For 6-7/7 marks: *Provides characteristics and features of the chemistry of fermentation and esterification&lt;sup&gt;1&lt;/sup&gt; *Includes two correct balanced chemical equations&lt;sup&gt;1&lt;/sup&gt; *Describes procedures in each of three steps including at least one diagram&lt;sup&gt;1&lt;/sup&gt; Question 21: (in chronologial order) *Lavoiser hypotheised that all acids contain oxygen. *Davy showed all acids contain hydrogen, rather than oxygen as Lavoiser hypotheised. *Arrehenius showed that acids ionise in water producing H&lt;sup&gt;+&lt;/sup&gt; ions as the only charged ions and bases ionise in water producing OH&lt;sup&gt;-&lt;/sup&gt; ions as the only charged ions. *Bronsted-Lowry therory says that acids are proton donors and bases are proton acceptors. Question 22: (a) 400 300 volume gas (m...
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## This document was uploaded on 09/19/2013.

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