Statement I: (S)-2-Bromobutane on treatment with SH⁻ at 50°C in DMSO gives inverted product

Statement II: This reaction follows S_N2 pathway

Both statement I and statement II are correct and statement II is the correct explanation of statement I

The answer is 1. Both statement I and statement II are correct and statement II is the correct explanation of statement I.

Statement I is correct because (S)-2-bromobutane is an optically active compound, and the S_N2 reaction with SH− at 50°C in DMSO is a concerted reaction that proceeds with inversion of configuration. This means that the product of the reaction will be the (R)-2-butanthiol.

Statement II is also correct because the S_N2 reaction is a nucleophilic substitution reaction that proceeds with the attack of a nucleophile on the back side of the electrophile. This attack results in the inversion of the configuration of the reactant.

Therefore, both statements I and II are correct, and statement II is the correct explanation of statement I.