Question

An aluminum atom has a mass of 4.48 * 10-23 g and a small airplane has a mass of 5000 kg. Use this information to answer the questions below. Be sure your answers have the correct number of significant digits.
What is the mass of 1 mole of aluminum atoms?
Round your answer to 3 significant digits.
_____g
How many moles of aluminum atoms have a mass equal to the mass of a small airplane?
Round your answer to 3 significant digits.
_______

Answer 1

Answer: 1. 26.9 g

2. $1.86\times 10^5moles$

Explanation:

According to avogadro's law, 1 mole of every substance weighs equal to the molecular mass and contains avogadro's number $6.023\times 10^{23}$ of particles.

1. 1 atom of aluminium has mass = $4.48\times 10^{-23}g$

Thus 1 mole or $6.023\times 10^{23}$ atoms has mass =$\frac{4.48\times 10^{-23}}{1}\times 6.023\times 10^{23}=26.9g$

2. 26.9 g of aluminium contains = 1 mole

5000 kg or 5000000 g of aluminium contains = $\frac{1}{26.9}\times 5000000=1.86\times 10^5moles$