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  /Title (electrolysis-gcse-chemistry.pdf)
  /Creator (Cheatography)
  /Author ({[}deleted{]})
  /Subject (Electrolysis - GCSE Chemistry Cheat Sheet)
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    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Electrolysis - GCSE Chemistry Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{{[}deleted{]}} via \textcolor{DarkBackground}{\uline{cheatography.com/56036/cs/15100/}}}
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  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 13th March, 2018.\\
   Page {\thepage} of \pageref{LastPage}.
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  Measure your website readability!\\
  www.readability-score.com
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\begin{document}
\raggedright
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% www.emerson.emory.edu/services/latex/latex_169.html
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\begin{multicols*}{2}

\begin{tabularx}{8.4cm}{x{4.16 cm} x{3.84 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Metal Ores}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Haematite}} & Iron (Fe2O3) \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
{\bf{Bauxite}} & Aluminium \tn 
% Row Count 2 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{8.4cm}}{{\bf{What are metal ores}}? \newline Naturally occurring compounds containing high percentages of specific metals. Desirable metals are extracted from ore.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Methods of Metal Extraction}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Depending on a metal's reactivity, different methods of extraction are used. \newline % Row Count 2 (+ 2)
If the metal is {\bf{less reactive than carbon}}, then a reduction reaction (involving carbon) is used. This works because the carbon forms compounds more readily, so it 'steals' the oxygen (similar to {\bf{displacement}} reactions). An example of this is iron, which is extracted using a blast furnace. \newline % Row Count 8 (+ 6)
If the metal is {\bf{more reactive than carbon}}, electrolysis must be used, as the metal's compounds are very stable. An example of this is aluminium extraction.% Row Count 12 (+ 4)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Aluminium Extraction}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{1. {\bf{Bauxite}} is purified to produce pure aluminium oxide (Al2O3). \newline % Row Count 2 (+ 2)
2. The aluminium oxide is dissolved in {\bf{cryolite}} (another aluminium ore). This introduces impurities, reducing the melting temperature of the mixture to 900\textasciicircum{}°C\textasciicircum{}. \newline % Row Count 6 (+ 4)
3. The aluminium oxide is melted. \newline % Row Count 7 (+ 1)
4. When a current is passed through it, the positive Al\textasciicircum{}3+\textasciicircum{} ions are attracted to the {\bf{cathode}} (negative electrode), where they gain electrons. This is {\bf{reduction}}. \newline % Row Count 11 (+ 4)
5. The negative O\textasciicircum{}2-\textasciicircum{} electrons are attracted to the {\bf{anode}} (positive electrons), where they lose electrons and form oxygen or carbon dioxide. This is {\bf{oxidation}}. \newline % Row Count 15 (+ 4)
Half equations: \newline % Row Count 16 (+ 1)
~ ~ Al\textasciicircum{}3+\textasciicircum{} + 3e\textasciicircum{}-\textasciicircum{} \{\{fa-arrow-right\}\} Al \newline % Row Count 18 (+ 2)
~ ~ 2O\textasciicircum{}2-\textasciicircum{} \{\{fa-arrow-right\}\} O2 + 4e\textasciicircum{}-\textasciicircum{}% Row Count 19 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{▪Electrolysis is possible because the molten aluminium oxide contains free electrons, allowing it to conduct electricity. \newline ▪ The electrodes are made of graphite because it is a good conductor. \newline ▪The anode must be replace regularly because it wears down through reactions with oxygen.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
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\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Iron Extraction}}  \tn
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\mymulticolumn{1}{x{8.4cm}}{{\bf{Reducing iron ore to iron}}: \newline % Row Count 1 (+ 1)
1. Hot air is added to the blast furnace, as this makes the coke burn faster and elevates the temperature to around 1500\textasciicircum{}°C\textasciicircum{}. \newline % Row Count 4 (+ 3)
2. The coke burns and produces carbon dioxide. \newline % Row Count 5 (+ 1)
~ C + O2 \{\{fa-arrow-right\}\} CO2 \newline % Row Count 6 (+ 1)
3. The carbon dioxide reacts with any unburnt coke. \newline % Row Count 8 (+ 2)
~ CO2 + C \{\{fa-arrow-right\}\} 2CO \newline % Row Count 9 (+ 1)
4. The carbon monoxide reduces the iron ore to iron. \newline % Row Count 11 (+ 2)
~ 3CO + Fe2O3 \{\{fa-arrow-right\}\} 3CO2 + 2Fe \newline % Row Count 12 (+ 1)
{\bf{Purifying the resulting iron}}: \newline % Row Count 13 (+ 1)
The main impurity is silicon dioxide (sand). \newline % Row Count 14 (+ 1)
1. Limestone is thermally decomposed into calcium oxide. \newline % Row Count 16 (+ 2)
~ CaCO3 \{\{fa-arrow-right\}\} CaO + CO2 \newline % Row Count 17 (+ 1)
2. Calcium oxide reacts with silicon dioxide to form slag. \newline % Row Count 19 (+ 2)
~ CaO + SiO2 \{\{fa-arrow-right\}\} CaSiO3% Row Count 20 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{▪Coke is almost pure carbon. \newline ▪Slag is used in road building and fertilisers.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}