Which of the following reagent is used with `KI` solution to give pure `HI`?

Which of the following reagents give lewisite?

Which of the following reagent is used as a refregerant ?

Which of the following reagent on treatment with KI gives iodine ?

Which of the following reagents can give urotopine?

Which of the following reacts with grignard reagent to give alkane:

Which of the following reagent give markovnikov product with propene:

Which of the following reagents can be used to distinguish between a sulphite and a sulphate in solution?