Answer:
an element is a pure substance which can not be spilt into simpler substances by chemical means
Explanation:
examples hydrogen, oxygen, copper
Waxes are considered to be important to living things, because waxes are a type of lipid. Lipids are energy stored within our body, somewhat like a storage of energy. Lipids, consists of other substances, such as oil, fats and the likes. Lipids store energy, for the cells to consume whenever they need it.
Answer:
Hydrogen disulfide
Explanation:
Hydrogen disulfide
, which is responsible for the rotten-egg scent, is toxic rather than simply smelly, if inhaled at concentrations above 700 parts per million.
It can be present at very low concentrations well below those considered to induce health effects. The scent of sulfide hydrogen does not affect your well-being.
