Final answer:
About 1.089 × 10^24 aluminum atoms are in 48.8 g of pure aluminum, calculated by converting the mass to moles using aluminum's molar mass and then converting moles to atoms using Avogadro's number.
Step-by-step explanation:
The question asks to calculate the number of atoms in 48.8 g of pure aluminum. To find this number, you need to first determine how many moles of aluminum are in 48.8 grams and then use Avogadro's number to convert moles to atoms.
To convert grams to moles, use the molar mass of aluminum, which is 26.98 g/mol. The calculation is as follows:
48.8 g Al × (1 mol Al / 26.98 g Al) = 1.809 moles Al (rounded to four significant figures)
Knowing that 1 mole of any substance contains 6.022 × 1023 atoms (Avogadro's number), we can now find the number of atoms:
1.809 moles Al × (6.022 × 1023 atoms/mol) = 1.089 × 1024 atoms Al
So, there are approximately 1.089 × 1024 aluminum atoms in a 48.8 g sample of aluminum.