We know because of DNA testing in general.
Answer: True
Air is a mixture of many things; it's not just Oxygen, but Hydrogen, Carbon, and Nitrogen as well are made up of air. Fun fact: Nitrogen is actually more abundant in air
ANSWER:
the answer is burning as it is a chemical change emaning that the substance changes chemically, the other choices are exp of physical changing meaning they stay the same substance but change physically
~batmans wife dun dun dun...aka ~serenitybella
An atom of Oxygen. Contains:
Protons = 8
Electrons = 8
Neutrons = Mass number - Number of protons = 18 - 8 = 10
Neutrons = 10.
