7. A+Barrow NC HCequiv CH(NaNH_(2))/(.)?xrightarrow [C](CH_(3)CH_(2)Cl)]_(2)?Bxrightarrow [Delta ](NaH_(2)C)C_(2)CH_(3)I_(2)I_(2)

This question is about organic chemistry, specifically about the reactions of alkynes. The first reaction is the addition of hydrogen cyanide (HC≡CH) to a compound A+B to form a new compound NC. The second reaction is the reaction of the compound formed in the first reaction with sodium amide (NaNH2) in the presence of a catalyst (C). The product of this reaction is a compound with a triple bond between two carbon atoms (CH3CH2C≡CCH3). The third reaction is the reaction of this compound with chloroethane (CH3CH2Cl) to form a new compound B. The fourth reaction is the reaction of compound B with sodium acetylide (NaC2) to form a compound with a triple bond between two carbon atoms (CH3CH2C≡CCH3). The final product is a compound with a triple bond between two carbon atoms (CH3CH2C≡CCH3).