Hydrocarbon, any of a class of organic chemical compounds composed only of the elements carbon (C) and hydrogen (H). The carbon atoms join together to form the framework of the compound; the hydrogen atoms attach to them in many different configurations. Hydrocarbons are the principal constituents of petroleum and natural gas.
Use slab in a sentence. 1  a piece that is flat, broad, and fairly thick: a slab of concrete, a slab of bread.  any of the rough, outer pieces cut from a log, as in sawing it into lumber.
a broad, flat, somewhat thick piece of stone, wood, or other solid material. a thick slice of anything: a slab of bread. a semifinished piece of iron or steel so rolled that its breadth is at least twice its thickness. a rough outside piece cut from a log, as when sawing one into boards.