Question

There are 0.92 moles of iron in a sample. What is the mass of the iron sample in grams?

A. 107.92
B. 55.84
C. 51.40
D. 1.84

Answer 1

To find the mass of 0.92 moles of iron, you need to multiply the number of moles by the molar mass of iron, which is 55.85 g/mol. Upon calculation, you get a mass of 51.38 grams, which rounds up to 51.40 grams, making option C the correct answer.

Step-by-step explanation:

To determine the mass of the iron sample in grams when you have 0.92 moles of iron, you use the molar mass of iron.

1. Find the molar mass of iron. The molar mass of iron (Fe) from the periodic table is 55.85 g/mol.
2. Calculate the mass of iron by multiplying the number of moles by the molar mass: Mass = moles × molar mass.

Now, doing the calculation:

Mass = 0.92 moles × 55.85 g/mol = 51.38 grams (rounded to two significant figures, it is 51.40 grams).

Therefore, the correct answer is C. 51.40 grams.