What is the full question?
Answer:
The period number tells which is the highest energy level occupied by the electrons.
Explanation:
- The period number (denoted by n) is the outer energy level that is occupied by electrons in an atom.
- The period number that an element is in, is the number of energy levels that the element has.
- When we move across a period from left to right in a periodic table the number of electrons in atoms increases within the same orbit.
A substance where almost all have the same atomic number of protons
Answer:
badc
Explanation:
the milky way is the biggest second is the solar system, third is the sun and last is the planet
True the answer came from a science book I have I will send you a link if needed