Question

Determine the number of grams in each of the quantities 1.39.0 x 1024 molecules Cl2

Answer 1

Mass of Cl₂ : 164.01 g

Further explanation

A mole is a number of particles(atoms, molecules, ions)  in a substance

This refers to the atomic total of the 12 gr C-12  which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles  

Can be formulated :

N = n x No

N = number of particles

n = mol

No = 6.02.10²³ = Avogadro's number

mol Cl₂ :

$\tt n=\dfrac{N}{No}\\\\n=\dfrac{1.39.10^{24}}{6.02.10^{23}}\\\\n=2.31$

mass Cl₂(MW=71 g/mol) :

$\tt mass=mol\times MW\\\\mass=2.31\times 71=164.01$