'This poisonous gas, element No. 9, is used in making freon & teflon'
fluorine
IT'S A GAS: This poisonous gas, element No. 9, is used in making freon & teflon
This poisonous gas, element No. 9, is used in making freon & teflon
This poisonous gas, element No. 9, is used in making freon & teflon
IT'S A GAS
fluorine
IT'S A GAS