Which of the molecules below is propyne? Two carbons are double bonded to each other; the pair is single bonded to H above left, below left, and below right, and to C H 3 above right. Two carbons are double bonded to each other; the pair is single bonded to C H 3 above left and right, and to H below left and right. An H is single bonded to C, which is triple bonded to another C, which in turn is single bonded to a C with H above and below and yet another C to the right; the final C is bonded to H above, below, and right. An H is single bonded to C, which is triple bonded to another C, which in turn is single bonded to a C which is bonded to H above, below, and right.