233. Which statement about the preparation of sodium metal in the Downs cell is incorrect? (1) Parts C and B of this cell are made of graphite and iron, respectively. (2) For every mole of sodium metal produced, half a mole of chlorine gas is formed. (3) The molten sodium obtained collects in vessel A inside the cell. (4) To lower the melting point of sodium chloride, calcium chloride is added to it. [Figure: Diagram of a Downs cell with parts labeled A, B, C]
\textbf{233.} Which statement about the preparation of sodium metal in the Downs cell is \textbf{incorrect}?
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(1) Parts C and B of this cell are made of graphite and iron, respectively.
(2) For every mole of sodium metal produced, half a mole of chlorine gas is formed.
(3) The molten sodium obtained collects in vessel A inside the cell.
(4) To lower the melting point of sodium chloride, calcium chloride is added to it.
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\textit{[Figure: Diagram of a Downs cell with parts labeled A, B, C]}
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