Question

Carl's chemistry teacher asked him to make a 1 M sodium chloride solution. Carl measured 58.44 grams NaCl, added it to a volumetric flask, and then added enough water to make a 1 liter solution. Carl's lab partner told him that he had made the 1 M solution incorrectly. How would you respond to her comment regarding Carl's lab technique?

Answer 1

After measuring the solute, Carl should first dissolve the solid in a small amount of DI water before diluting to the total volume.

Step-by-step explanation:

To ensure that all the solute dissolves in the solution, first dissolve the solid in less than the total volume of solution needed.

Answer 2

Molarity is the moles of solute dissolved in 1 liter of the solution.

1 M NaCl solution is 1 moles of NaCl in 1 L of the solution.

Here the solute is NaCl and its molar mass is 58.44 g/mol. So measuring out 58.44 g of NaCl gives 1 moles of NaCl. Carl then added water to bring the volume up to 1 Liter. Carl's lab technique is correct.