Question

What is the total number of moles of NaCl(s) needed to make 3.0 liters of a 2.0 M NaCl solution?
(1) 1.0 mol (3) 6.0 mol
(2) 0.70 mol (4) 8.0 mol

Answer 1

The number of moles of NaCl(s) needed to make 3.0 L of a 2.0 M NaCl solution (soln) is:
3.0 L NaCl soln* (2.0 mol NaCl/ 1L NaCl soln)= 6.0 mol NaCl.

Therefore, (3) 6.0 mol is the correct answer.

Hope this helps~

Answer 2

The total number of moles of NaCl needed to make 3 liters of a 2.0 M NaCl solution is equal to 6.0 mol (3).

First, to calculate the concentration of a solution it is necessary to use the following expression:

                                           $C = mol/vol$

So, just add the given values ​​and find the required amount of mole:

 

                                         $2 = x/3$

                                       $x = 6 moles$

Thus, 6 mol of NaCl are needed to create a 3 liter solution with 2 M (moles per liter) concentration.

Learn more about mole calculation in: brainly.com/question/15693285