Question

How many milliliters of 0.400 M solution can be prepared by dissolving 5.00 g of NaBr in water? __________mL

Answer 1

To prepare a 0.400 M solution from 5.00 g of NaBr, first calculate the moles of NaBr and then use the molarity to determine the volume, which yields 121.5 mL of the solution.

Step-by-step explanation:

To calculate how many milliliters of a 0.400 M solution can be prepared by dissolving 5.00 g of NaBr in water, we need to follow these steps:

1. Determine the molar mass of NaBr. Sodium (Na) has an atomic mass of roughly 22.99 g/mol, and bromine (Br) has an atomic mass of roughly 79.90 g/mol, giving NaBr a molar mass of 22.99 g/mol + 79.90 g/mol = 102.89 g/mol.
2. Calculate the number of moles of NaBr that corresponds to 5.00 g. Using the formula:
   moles = mass (g) / molar mass (g/mol), we find that moles of NaBr = 5.00 g / 102.89 g/mol = 0.0486 mol.
3. Finally, use the desired molarity to find the volume in liters and then convert to milliliters. Molarity (M) = moles of solute / volume of solution (L), so volume of solution (L) = moles of solute / Molarity (M). Therefore, volume of solution = 0.0486 mol / 0.400 M = 0.1215 L or 121.5 mL.

Thus, you can prepare 121.5 mL of a 0.400 M NaBr solution with 5.00 g of NaBr.