Hoʻokaʻawale ʻia nā kukui pahū i ʻekolu papa: IIA, IIB, a me IIC.
Papa IIA
He kūpono no nā wahi me nā mea e like me ka ʻaila, e like me nā hale hau. ʻO ke kinoea hōʻike no kēia ʻāpana he propane.
Papa IIB
Hoʻohana ʻia i nā hale hana maʻamau i loaʻa nā kinoea weliweli. Ethylene ʻo ia ke kinoea hōʻike no kēia hoʻohālikelike.
Papa IIC
Hoʻolālā ʻia no nā hale hana i ʻike ʻia hydrogen, acetylene, a i ʻole carbon disulfide.