How to do this: how many grams are in 1.946 moles of nacl

Its simple. You use the molar mass on the periodic table to calculate the molar mass of NaCl. The molar mass of Na is 22.99 and the molar mass of Cl is 35.45. 

22.99+35.45=58.44g

There are 1.946 moles, so you multiply 1.946 moles and 58.44 moles/gram to get 113.72 g.
This works because when you multiply, the mole units cancel out and you get the grams as units.

113.72g

ps: try to solve this problem by yourself to make sure you actually understand the concept. 

To find the grams when you have moles you have to multiply the moles by molar mass of NaCl. NaCl's molar mass is Na- 22.99 + Cl-35.45 (atomic masses) = 58.44. So multiply 1.946 by 58.44 and you get 113.72424grams (don't know how far you round).
To find molecules, atoms or ions.
If you start out with grams divide by molar mass and you get moles to go to atoms multiply the moles by Avogadro constant (6.02X10^23) and you get atoms/ions/molecules.
So if you go into moles you divide and if you go out you multiply.
Here is the chart that we learned how to do moles.

Atoms )>(divide by Avogadro constant)-Moles>(multiply by molar mass)-Grams-
Ions)<(multiply by Avogadro constant)-Moles-<---(divide by molar mass)-Grams-

For the difference between moles and molecules
An atom is a basic unit of matter. A molecule would be a collection of atoms. Like H2O- it has two hydrogen atoms and one oxygen atom and that makes a water molecule.
A mole is a number saying how many atoms are in the substance. One mole has 6.02X10^23 atoms. So one mole of Oxygen weighs 16 grams. 2 would weigh 22grams. So in two moles there is 2(6.02X10^23)
Hope This Helped

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.