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DIFF Subgroup
C01B 21/20

Nitrogen oxides; Oxyacids of nitrogen; Salts thereof

Introduced: September 1968

Full Title

Nitrogen; Compounds thereof > Nitrogen oxides; Oxyacids of nitrogen; Salts thereof

Of 9 combined children, 7 exist in both systems.

2 codes are CPC-only extensions.

4 shared codes have differing titles between IPC and CPC.

Child Classifications

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  • C01B 21/203 CPC only CPC only
  • C01B 21/206 CPC only CPC only
  • C01B 21/22 Nitrous oxide (N2O) IPC+CPC Available in IPC and CPC
  • C01B 21/34 Nitrogen trioxide (N2O3) IPC+CPC Available in IPC and CPC
  • C01B 21/36 Nitrogen dioxide (NO2, N2O4) ( , C01B21/26, C01B21/30 take precedence) IPC+CPC Available in IPC and CPC
  • C01B 21/48 Methods for the preparation of nitrates in general (particular individual nitrates, see the relevant groups of subclasses C01B - C01G, according to the cation) IPC+CPC Available in IPC and CPC
  • C01B 21/50 Nitrous acid; Salts thereof IPC+CPC Available in IPC and CPC