All around us are natural or artificial compounds (excepting elements).
Yes, "useful" is a compound word made up of the root word "use" and the suffix "-ful" which means "full of."
water
family
Carbon tetrachloride, a useful but toxic solvent.
like in pools, it keeps em clean ;]
For example the melting point.
Sulfur dioxide is the name of the compound with the chemical formula SO.
A compound miter saw can cut two angles at the same time. Very useful when cutting crown molding.
Because they are useful.
Compound as it does have a unneeded ending. "and is quite useful". Meaning that the sentence does make sense with out that part of the sentence. If it didn't have this extra bit it would be a simple sentence.
The maximum useful magnification of a compound light microscope is typically around 1000x. Beyond this point, image quality decreases due to limitations in the lens quality, resolution power, and diffraction of light.
Examples: methane, starch, sucrose, ethanol, oil, greases, dyes, etc.