Answer:
There are approximately 1.43 x 10^23 bromine atoms in 30.1 g of CH2Br2.
Step-by-step explanation:
Calculate the molar mass of CH2Br2:
M(CH2Br2) = M(C) + 2M(H) + 2M(Br)
M(CH2Br2) = 12.01 g/mol + 2(1.01 g/mol) + 2(79.90 g/mol)
M(CH2Br2) = 252.82 g/mol
Calculate the number of moles of CH2Br2:
n = m/M
n = 30.1 g / 252.82 g/mol
n = 0.119 mol
Determine the number of bromine atoms:
There are 2 bromine atoms in each molecule of CH2Br2, so we can use Avogadro's number to convert moles to atoms:
N = n * N_A * 2
N = 0.119 mol * 6.022 x 10^23 atoms/mol * 2
N = 1.43 x 10^23 bromine atoms