Final answer:
To determine how many moles of PBr3 are in 4.36 g, divide the mass of PBr3 by its molar mass (176.124 g/mol), which yields approximately 0.02475 moles.
Step-by-step explanation:
To find out how many moles of PBr3 are in 4.36 g of this compound, we use the molar mass of PBr3. We have been given the molar mass: 176.124 g/mol. The formula to calculate moles is:
Number of moles = mass of the substance (g) / molar mass of the substance (g/mol).
In this case, the calculation would be:
Number of moles of PBr3 = 4.36 g / 176.124 g/mol.
Calculating this, we get:
Number of moles of PBr3 = 0.02475 moles (approximately).