Below is a simplified diagram of the Downs cell in which sodium metal is manufactured.

Below is a simplified diagram of the Downs cell in which sodium metal is manufactured.




(i) Identify electrolyte X and gas Y.

(ii)Give two properties of sodium that make it possible to collect as shown above.

(iii) Why is graphite preferred to steel as the anode?

(iv) Explain how sodium hydroxide pellets would be obtained from sodium amalgam?

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i)
X – Molten sodium chloride
gas Y - Chlorine
ii) Less dense than molten sodium Chloride
Has low melting point
Crystallises faster than calcium

(iii) At high temperature, steel would react with chlorine formed, but graphite is inert even at high temperature

(iv) Add water then evaporate to form sodium hydroxide (NaOH)

2NaHg(l) + 2H2O(l) // 2NaOH(ag) + 2Hg(s) + H2(g)

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marto answered the question on September 17, 2019 at 08:19

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