Final answer:
About 4.8024 grams of NaHSO4 are needed to prepare 100 mL of a 0.400 M solution, calculated by first finding the moles needed and then converting this to mass using the molar mass of NaHSO4.
Step-by-step explanation:
To calculate the mass of NaHSO4 required to prepare a 0.400 M solution, we first need to determine the number of moles of NaHSO4 needed for 100 mL (0.100 L) of the solution. Using the equation M = moles/Liter, where M is the molarity (0.400 M), we can find the moles as follows: 0.400 moles/L × 0.100 L = 0.040 moles. The molar mass of NaHSO4 is needed to convert moles to grams.
The molar mass of NaHSO4 is approximately 120.06 g/mol.
Now we can calculate the mass in grams by multiplying the number of moles by the molar mass: 0.040 moles × 120.06 g/mol = 4.8024 g. Therefore, 4.8024 grams of NaHSO4 are required to prepare exactly 100 mL of a 0.400 M solution.