Amongst the following the total number of compounds whose aqueous solution turns red litmus paper blue is
KCN, K₂SO₄, (NH₄)₂C₂O₄, NaCl, Zn(NO₃)₂, FeCl₃, K₂CO₃, NH₄NO₃ and LiCN

The reagent(s) used for softening the temporary hardness of water is (are)

The total number of cyclic isomers possible for a hydrocarbon with the molecular formula C₄H₆ is

The synthesis of 3-octyne is achieved by adding a bromoalkane into a mixture of sodium amide and and alkyne