Answer:
19.11g
Step-by-step explanation:
mole = mass ÷ molar mass
mole = 2.61 ÷ 27
mole = 0.097mol
Number of atoms in 2.61g of Aluminum = 6.022 × 10^23 × 0.097
= 0.584 × 10^23
= 5.84 × 10^22atoms
To get the same number of atoms for Gold (Au), we multiply the atomic mass of Au by 0.097mol
Atomic mass of Au = 197g/mol
mass = mole × molar mass
mass = 0.097 × 197
mass = 19.109g
mass = 19.11g