what is oxygen?
what is carbondioxide?
what is helium?
what is
Answers
Answer:
a colourless, odourless reactive gas, the chemical element of atomic number 8 and the life-supporting component of the air.
a colourless, odourless gas produced by burning carbon and organic compounds and by respiration. It is naturally present in air and is absorbed by plants in photosynthesis.
the chemical element of atomic number 2, an inert gas which is the lightest member of the noble gas series.
Explanation:
Answer:
(1)Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds.
(2)a gas that has no colour or smell that people and animals breathe out of their lungs
(3)a very light colourless gas that does not burn, often used to fill objects that float in the air (balloons)
(4)