(Note to the student: This problem previews an important aspect of Chapter 9 and is well w...

(Note to the student: This problem previews an important aspect of Chapter 9 and is well worth attempting in order to get a head start on the material presented there.)

Alkynes of the type RC≡CH may be prepared by nucleophilic substitution reactions in which one of the starting materials is sodium acetylide

(a) Devise a method for the preparation of CH3CH2C≡CH from sodium acetylide and any necessary organic or inorganic reagents.

(b) Given the information that the pKa for acetylene (HC≡CH) is 26. comment on the scope of this preparative procedure with respect to R in RC≡CH. Could you prepare (CH3)2CHC≡CH or (CH3)3CC≡CH in good yield by this method?