While titrating dilute HCl solution with aqueous NaOH, which of the following will not be required?

The IUPAC name for the following compound is

For the following Assertion and Reason, the correct option is

Assertion (A): When Cu (II) and sulphide ions are mixed, they react together extremely quickly to give a solid.

Reason (R): The equilibrium constant of
Cu²⁺(aq) + S^2–(aq) ⇌ CuS(s) is high because the solubility product is low.

Which of the following compunds will show retention in configuration on nucleophilic substitution by OH^– ion?