7) Determine the number of tin atoms in 7.5 moles of tin.

The molar mass of tin is 118.71 g/mol

4.5 x 10^24 atoms of tin

Explanation:

We do not need to use the molar mass because we only need to know that 1 mol of something = 6.022 x 10^23 atoms of that thing.

7.5 mol tin x (6.022 x 10^23 atoms/1 mol tin)