CH3 - CH2 - C ≡ CH (1- butyne)
CH3 - C ≡ C- CH3 (2- butyne)
In 1-butyne, terminal carbon atom contains atom one acidic hydrogen, therefore it will react with silver nitrate in the presence of ammonium hydroxide to give silver butynide. Whereas 2-butyne does not undergo such type of the reaction, because of the absence of acidic hydrogen.
