The set-up below (Figure 2) was used to electrolyse a bromide of metal D, DBr2.

The set-up below (Figure 2) was used to electrolyse a bromide of metal D, DBr2.

a) Write the equation for the reactions at the I. Cathode II. Anode
b) The electrodes used in the experiment were made of carbon and metal D. Which of the two electrodes was used as the anode? Give a reason
c) Give a reason why this experiment is carried out in a fume cupboard.

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a) I. $D^{2+}_{(l)} + 2e^- \rightarrow D_{(s)}$

II. $2Br^-(l) \rightarrow Br^-(l) \rightarrow Br_2(g) + 2e^-$

b) Carbon : It will not be attacked by bromine gas and D reacts with bromine vapour

c) Bromine gas is poisonous or toxic

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johnmulu answered the question on May 15, 2017 at 08:51

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