Final answer:
To provide 40.5 g of KBr in a 0.716 M KBr solution, you will need a volume of 0.478 L or 478 mL.
Step-by-step explanation:
To calculate the volume of a 0.716 M KBr solution needed to provide 40.5 g of KBr, we can use the formula:
Molarity (M) = moles of solute / volume of solution (L)
First, we need to calculate the moles of KBr:
moles = mass / molar mass
molar mass of KBr = 39.10 g/mol + 79.904 g/mol = 118.014 g/mol (atomic masses of K = 39.10 g/mol and Br = 79.904 g/mol)
moles = 40.5 g / 118.014 g/mol = 0.343 mol
Next, we can rearrange the formula to solve for the volume:
volume = moles of solute / Molarity
volume = 0.343 mol / 0.716 M = 0.478 L or 478 mL