Answer:
the right side of the periodic table are metals while the left side are non metals (with the exception of hydrogen)
Answer is: one electron in the first three orbitals, none in the fourth or fifth orbitals. All three electrons will have parallel spins (unpaired electrons).
This is Hund's rule - orbitals of the same energy are each filled with one electron before filling any with a second, these first electrons have the same spin.
The answer is the trachea
Answer: 3.0 moles of water
are needed to react with a mole of 3.0 of Na
Explanation:
The balanced chemical reaction of sodium with water is as follows:

According to stoichiometry:
2 moles of sodium
reacts with = 2 moles of water 
Thus 3.0 moles of sodium
reacts with =
moles of water 
3.0 moles of water
are needed to react with a mole of 3.0 of Na