Final answer:
The mass of 3.99 mol of nickel is calculated by multiplying the number of moles by the molar mass of nickel (58.693 g/mol), resulting in a mass of 234.18 grams.
Step-by-step explanation:
To calculate the mass of 3.99 mol of nickel (Ni), we use the molar mass of nickel. From the periodic table, we know that the molar mass of nickel is 58.693 grams per mole (g/mol).
The calculation involves simply multiplying the number of moles by the molar mass of nickel:
Multiply the number of moles of Ni (3.99 mol) by the molar mass of Ni (58.693 g/mol).
Mass of nickel = 3.99 mol × 58.693 g/mol = 234.18407 grams.
Note that the mol units cancel algebraically, thus giving us the mass in grams. The final answer is the mass of 3.99 mol of nickel which is 234.18 grams (rounded to two decimal places).