Answer:
An oxygen atom is what is found on the periodic table. The Oxygen atom is made of 8 proton, 8 electrons and generally 8 neutrons.The oxygen molecule is made of two oxygen atoms that have formed a double bond with each other and share valence electrons.
Explanation:
They live in groups for protection from predators could be one
Answer:
Bacteriophage: A virus that infects bacteria, also called a phage.
Explanation:
Simple. Air has mass. And if air has mass it also has weight. You can feel air when the wind blows. Or do an experiment. Weigh an empty container. Then pump it to a vacuum. Weigh it again. The difference is the weight of the air inside.