An aliphatic compound is used in chemistry. It is highly flammable and can be used in petroleum. Methane is the simplest aliphatic compound. It is also used in welding.

An alkylmetal is an aliphatic organometallic compound.

Yes, aliphatic compounds are harmful because they are very flammable. This compound is used often as fuel in Bunsen burners and welding.

Aliphatic compounds are typically comprised of carbon and hydrogen atoms joined together straight chains, branched chains, or non-aromatic rings. They can also contain other elements such as oxygen, sulfur, chlorine, or nitrogen and are often flammable. Methane is the simplest aliphatic compound.

Aromaticity doesn't require a compound to have a detectable olfactory response although some aromatic compounds do have a smell.

Ethanol is an aliphatic compound because it has a chain like structure with no benzene ring.