Answer:
NaBH4
H3O+
Step-by-step explanation:
The conversion of 3-pentanone to form 3-pentanol is a reduction reaction. The first step of the reaction is the transfer of a hydride ion to the carbonyl from the reducing agent sodium borohydride.
After the transfer of the hydride ion, transfer of a proton from H3O+ completes the reaction mechanism hence 3-pentanol is formed from 3-pentanone.