Answer:
2
Explanation:
CO₂ shows that there are 2 oxygen molecules. Also, the name Carbon Dioxide. This shows there is One Carbon and Two Oxygen molecules from the naming system.
Answer: the answer is B estimation
Explanation:
i just took a test
He proposed that energy levels of electrons are discrete and that the electrons revolve in stable orbits around the atomic nucleus but can jump from one energy level (or orbit) to another.
Elements are ordered from left to right, increasing atomic number as they go. The periodic table allows us to find out and predict things about elements that haven’t been discovered yet!