The mechanism of S_N 1 reaction is given as: R-X → Ion pair R^ X^ → Solvent Separated ion pair R^ ∥ X^ → Y^ R-Y+X^ A student writes general…

The mechanism of $\displaystyle \mathrm{S}_{\mathrm{N}} 1$ reaction is given as :

$$R-X \rightarrow \underset{\text { Ion pair }}{R^{\oplus} X^{\ominus}} \rightarrow \underset{\substack{\text { Solvent } \text { Separated ion } \text { pair }}}{R^{\oplus} \| X^{\ominus}} \xrightarrow{Y^{\ominus}} R-Y+X^{\ominus}

$$A student writes general characteristics based on the given mechanism as :

The reaction is favoured by weak nucleophiles.

$\displaystyle \mathrm{R}^{\oplus}$ would be easily formed if the substituents are bulky.

The reaction is accompanied by racemization.

The reaction is favoured by non-polar solvents.

Which observations are correct ?