sentences:  If no additional nucleic acids are present, then [A], [B], and [AB] will be equal, and equal to half the initial concentration of double-stranded nucleic acid, [AB]initial.This gives an expression for the melting point of a nucleic acid duplex of
  
  formula_3.Because Δ"G"° = Δ"H"° -"T"Δ"S"°, "T"m is also given by
  
  formula_4.