Why is air considered as a pure substance only when it is in gaseous form?​

increased stability in the completion of fluorine's outer shell.

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.