Final answer:
Diluting 1.00 mL of a NaCl solution to 1.80 L results in the decrease of the solution's molarity while the number of moles and mass of NaCl stay the same.
Step-by-step explanation:
Understanding Dilution of Solutions
When 1.00 mL of a NaCl solution is diluted to 1.80 L, the number of moles of NaCl (the solute) remains the same, but the overall volume of the solution increases. This means that the concentration (molarity) of the NaCl solution decreases because molarity is defined as the number of moles of solute per liter of solution (moles/L). As the volume of the solvent (water) is increased to dilute the solution, the same amount of solute (NaCl) is now spread throughout a greater volume, resulting in a lower concentration.
Let's consider constants in this process. The mass of NaCl in the solution and the total number of moles of NaCl present do not change during the dilution process. However, the molarity of the NaCl solution changes because molarity is dependent on the volume of the solution, and the volume is being increased.