D) Critical thinking. You thought about what both things said, and thought about which one that you thought was right. Hope this helps. Please mark brainliest. Have an amazing night.
He is WRONG
Explanation:
Any atom at the ground state has its orbital levels fill from the bottom (close to the nucleus) – up. The inner orbitals are of lower energy state and fill first because the atoms ‘likes’ to exist in the low energy and more stable state. Only when the atom is in an excited state do some of the electrons in the lower orbital levels shift to higher unfilled orbitals.
Answer:
Q2->They all form acids when combined with hydrogen. They are all fairly toxic. They readily combine with metals to form salts.
Q3->Because their outermost orbit is complete. In Mendeleev's original periodic table there was no place reserved for noble gas. They were discovered in end of 19th century. So Mendeleev created zero group without disturbing original periodic table.
Explanation: