Answer:
A
Explanation:
The purpose of the periodic table was to organize elements as they were discovered into periods and groups, according to their properties. It was not just a naming of elements, as a list.
Answer:
electrons move around the nucleus in fixed orbits of equal amounts of energy
Explanation:
Quantum Theory
The balanced equation is attached in the image below. The coefficients are 2, 2, blank.
Answer: An electron will jump to a higher energy level when excited by an external energy gain such as a large heat increase or the presence of an electrical field, or collision with another electron.
Explanation: