title: C2H2
text: # C2H2
  
  C2H2 may mean:
  
  ## Molecular formulae
  
  The molecular formula $C_2H_2$ (molar mass: 26.04 g/mol, exact mass: 26.01565 u) may refer to:
  
  * Acetylene (or ethyne)
  * Methylidenecarbene
  * Vinylidene group
  
  ## Transcription factors
  
  * C2H2 zinc finger, short for $Cys_2His_2$ a class of transcription factors with the small protein structural motif stabilised with Zinc ions
  