You add 0.5 moles of NaCl to water to make a 250 mL solution. What is the molarity
of this solution?
0 4.0M
1.0 M
2.0 M
2.5M

The correct answer is 2, 0M

Explanation:

We calculate the molarity, which is a concentration measure that indicates the moles of solute (in this case NaCl) in 1000ml of solution (1 liter):

250 ml solution 0,5 moles of NaCl

1000 ml solutionx= (1000 ml solution x 0,5 moles of NaCl)/250 ml solution

x=  2,0 moles of NaCl --> The solution is 2 M

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