Kev tawg-pov thawj teeb tau muab faib ua ob peb theem

Kev tawg-pov thawj teeb pom kev zoo tau muab faib ua peb pawg: IIA, IIB, thiab IIC.

Class IIA

Haum rau cov chaw nrog roj av-zoo li cov tshuaj, xws li chaw nres tsheb roj. Cov roj sawv cev rau pawg no yog propane.

Class IIB

Siv nyob rau hauv dav dav qhov teeb meem uas muaj kev phom sij yog tam sim no. Ethylene yog tus sawv cev roj rau qhov kev faib tawm no.

Hoob IIC

Tsim los rau cov ntaub ntawv raug rau hydrogen, acetylene, los yog carbon disulfide.