Smell of bitter almonds is seen in poisoning with
Cyanide can be a colorless gas, such as hydrogen cyanide (HCN) or cyanogen chloride (CNCl), or a crystal form such as sodium cyanide (NaCN) or potassiumcyanide (KCN). Cyanide sometimes is described as having a "bitter almond" smell, but it does not always give off an odor, and not everyone can detect this odor. Ref ganong's review of medical physiology 25e p143
Phosphorus
Hydrocyanic acid
Nitric acid
Oxalic acid
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