Acetylene or ethyne(systematic name) are weakly acidic nature I give you example about mono alkaline reactions (NOTE: hear I mentioning as" triple bond" its abcarbon–carbon triple bond places all four atoms in the same straight line, with CCH bond angles of 180 degree angle) // CH "triple bond"CH + NaNH2 ----> H – C " triple bond"C Na+ + 1/2 H2// //CH "triple bond" CH + 2[Cu(NH3)2]Cl ———→ Cu – C "triple bond"C – Cu + 2NH4Cl + 2NH3//