AQA AS Jun 2016 Paper 2 Q8

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18When an aqueous solution of ethanoic acid reacts with magnesium, the progress of reaction can be followed using the equipment shown in Figure 5 to measure the volume of hydrogen produced. Figure 5 Figure 6 shows how the volume of hydrogen produced varies with time when 396 mg of magnesium are added to 30.0 cm3 of 0.600 mol dm3 ethanoic acid. Time M/JUN16/7404/2 Figure 6 Volume of hydrogen *18*<br />
 190 8 . 1 The equation for the reaction between ethanoic acid and magnesium is shown. 2CH3COOH(aq) + Mg(s)(CH3COO)2Mg(aq) + H2(g) With the aid of calculations, show that the magnesium is in excess in this reaction. [3 marks] 0 8 . 2 The reaction was repeated using 20 cm3 of 0.800 mol dm3 of ethanoic acid solution with all other conditions the same. The magnesium was still in excess. Sketch a line on Figure 6 to show how the volume of hydrogen produced varies with time in this second experiment. [2 marks] Space for working. Turn over for the next question *19* Turn overM/JUN16/7404/2<br />

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