s ▁one ▁stable ▁is ot ope , ▁ 7 5 As . ▁In ▁these ▁circumstances ▁Ar O + ▁may ▁be ▁removed ▁by ▁reaction ▁with ▁N H 3 . ▁Alternatively ▁electro ther mal ▁v apor ization ▁or ▁using ▁hel ium ▁gas ▁can ▁avoid ▁these ▁inter ference ▁problems . ▁Arg on ▁can ▁also ▁form ▁an ▁an ion ▁with ▁ch lor ine , ▁Ar Cl − , ▁though ▁this ▁is ▁not ▁a ▁problem ▁for ▁mass ▁spect rom etry ▁applications ▁as ▁only ▁c ations ▁are ▁detected . ▁ ▁The ▁arg on ▁b ory ni um ▁ion , ▁B Ar + ▁is ▁produced ▁when ▁B Br + ▁at ▁energ ies ▁between ▁ 9 ▁and ▁ 1 1   e V ▁react s ▁with ▁arg on ▁atoms . ▁ 9 0 % ▁of ▁the ▁positive ▁charge ▁is ▁on ▁the ▁arg on ▁atom . ▁ ▁Ar C + ▁ ions ▁can ▁be ▁formed ▁when ▁arg on ▁ ions ▁impact ▁carbon ▁mon ox ide ▁with ▁energ ies ▁between ▁ 2 1 ▁and ▁ 6 0   e V . ▁However ▁more ▁C + ▁ ions ▁are ▁formed , ▁and ▁when ▁the ▁energy ▁is ▁on ▁the ▁high ▁side , ▁O + ▁is ▁higher . ▁ ▁Ar N + ▁can ▁form ▁when ▁arg on ▁ ions ▁impact ▁d init ro gen ▁with ▁energ ies ▁between ▁ 8 . 2 ▁and ▁ 4 1 . 2   e V ▁and ▁pe aking ▁around ▁ 3 5   e V . ▁However ▁far ▁more ▁ ▁and ▁N + ▁are ▁produced . ▁ ▁Ar X e