Chemistry · Oct / Nov 2021 · Paper 41 · Question 3
0620
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The question as text
This question is about electrolysis. Concentrated hydrochloric acid is electrolysed using the apparatus shown. concentrated hydrochloric acid carbon electrodes wire + –
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3(a)(i)[2]
2Cl – → Cl 2 + 2e–
Cl 2 (1)
rest of equation (1)
3(a)(ii)[1]
Oxidation AND lose electrons
3(b)[1]
effervescence (of colourless gas)
3(c)[2]
2H+ + 2e– → H2
H+ + e as only species on LHS (1)
rest of equation fully correct (1)
3(d)(i)[1]
1
3(d)(ii)[2]
M1 increase (1)
M2 H+ ions being removed (1)
3(e)[2]
M1 cathode: silver / grey solid (1)
M2 anode: bubbles of orange / brown gas (1)
3(f)[2]
M1 inert (1)
M2 conducts electricity (1)
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