Question

A chemist weighed out 62.3 g of iron. Calculate the number of moles of iron she weighed out. Be sure your answer has the correct number of significant digits.

Answer 1

The chemist weighed out 1.115 moles of iron, calculated by dividing the mass of iron (62.3 g) by its molar mass (55.85 g/mol) and rounding to three significant figures.

Step-by-step explanation:

To calculate the number of moles of iron a chemist weighed out, we must first know the molar mass of iron. The molar mass of iron is 55.85 g/mol. Using the formula:

Number of moles = Mass / Molar mass,

we find:

Number of moles of iron = 62.3 g / 55.85 g/mol = 1.115 mol (rounded to three significant figures).

Therefore, the chemist weighed out 1.116 moles of iron.