Suggest a suitable method of preparation of the salts A, B, C and D (do not describe, give only balanced chemical equations).
(i) A is a sodium salt.
(ii) B is an insoluble salt.
(iii) C is a soluble salt of copper.
(iv) D is a soluble salt of zinc.

Explanation

To prepare the salts A, B, C, and D, we can use the following balanced chemical equations:

(i) For salt A (sodium salt):
\[ \text{NaOH} + \text{HCl} \rightarrow \text{NaCl} + \text{H}_2\text{O} \]

(ii) For salt B (insoluble salt):
\[ \text{Pb(NO}_3\text{)}_2 + 2 \text{NaCl} \rightarrow \text{PbCl}_2 \downarrow + 2 \text{NaNO}_3 \]

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