In this question, we are asked to convert from moles to grams.
We have 2.40 moles of NaCl.
We need the molar mass of NaCl. We can calculate this by referencing the periodic table and looking up the atomic weight.
Na = 22.99g
Cl = 35.45g
----------------
+ 58.44g
2.40 moles x (58.44grams) / (1 mole) = 140.26 grams of NaCl
There are 140.26 grams in 2.40 moles of NaCl.