Final answer:
The mass of a pure gold coin containing 0.140 mol of gold is calculated using the molar mass of gold from the periodic table (196.97 g/mol), resulting in a mass of 27.576 grams.
Step-by-step explanation:
To calculate the mass of a pure gold coin that contains 0.140 mol of gold, one must use the concept of molar mass. Molar mass is the mass of one mole of a substance. The periodic table indicates that the molar mass of gold (Au) is 196.97 g/mol. Therefore, the mass of the coin can be calculated using the formula:
Mass = (Number of moles) × (Molar mass of the substance)
For gold, this calculation will be:
Mass = 0.140 mol × 196.97 g/mol
After performing the multiplication, the mass of the pure gold coin is found to be:
Mass = 27.576 g
This mass represents the amount of gold in the coin.