To determine the number of Cobbert atoms in 345 g of Cobbert, we need to first calculate the number of moles of Cobbert in 345 g using the molar mass of Cobbert.
The molar mass of Cobbert (CoBr) = atomic mass of Cobalt (Co) + atomic mass of Bromine (Br)
= 58.9332 g/mol + 79.904 g/mol
= 138.8372 g/mol
Number of moles = mass / molar mass
Number of moles = 345 g / 138.8372 g/mol = 2.483 moles
Now, to find the number of Cobbert atoms in 2.483 moles, we use Avogadro's number:
1 mole of any substance contains Avogadro's number of particles (6.022 x 10^23)
Number of Cobbert atoms = number of moles x Avogadro's number
Number of Cobbert atoms = 2.483 moles x 6.022 x 10^23 atoms/mol = 1.495 x 10^24 Cobbert atoms
Therefore, there are approximately 1.495 x 10^24 Cobbert atoms in 345 g of Cobbert.