Final answer:
The mass of 752 atoms of lithium is 8.663 × 10^-21 grams, calculated by dividing the molar mass of lithium by Avogadro's number to find the mass of one atom and then multiplying by the total number of atoms.
Step-by-step explanation:
To calculate the mass of 752 atoms of lithium (Li), we use the molar mass of lithium and Avogadro's number. One mole of lithium weighs 6.94 grams and contains 6.022 × 1023 atoms. To find the mass of 752 atoms, we first find the mass of one atom and then multiply by the number of atoms.
- Determine the mass of one Li atom by dividing the molar mass of Li by Avogadro's number:
- Mass of 1 atom of Li = (6.94 g/mol) / (6.022 × 1023 atoms/mol) = 1.152 × 10-23 g
- Multiply the mass of one atom by the total number of atoms:
- Mass of 752 Li atoms = 1.152 × 10-23 g/atom × 752 atoms = 8.663 × 10-21 g
Therefore, the mass of 752 atoms of lithium is 8.663 × 10-21 grams.