Calculate the mass of a sample of cobalt containing 3.31x10^22 atoms

Mass = 3.24 g

Explanation:

Given data:

Number of atoms of cobalt = 3.31 × 10²² atoms

Mass of cobalt atoms  = ?

Solution:

We will calculate the number of moles of cobalt by using Avogadro number.

1 mole contain 6.022× 10²³ atoms

3.31 × 10²² atoms  × 1 mol / 6.022× 10²³ atoms

0.549 mol × 10⁻¹

0.0549 mol

Mass of cobalt:

Mass = number of moles × molar mass

Mass = 0.0549 mol × 58.93 g/mol

Mass = 3.24 g

here we have to get the change of moles on decrease the volume of the reaction in gas phase.

the   per the given options it will decrease by (d) 11-50%

we know, on decreasing the volume of the gas phase reaction the reaction moves to the product side.

the reaction:                     so₂cl₂ (g) = so₂ (g) + cl₂ (g)         total

the moles at equilibrium:   1 - α                 α               α           = 1+α

concentrations:                   1 - α               α               α           = 1 + α

(concentration = moles/volume, as volume is 1 l)

(where α is the degree of dissociation)

now the dissociation constant in terms of concentration is :

=  

or,

or,   = (at v = 1l)

the reaction:                     so₂cl₂ (g) = so₂ (g) + cl₂ (g)         total

the moles at equilibrium:   1 - α                 α               α           = 1+α

concentrations:               (1 - α)/0.5           α/0.5         α/0.5       = (1 + α)/0.5

thus, the dissociation constant in terms of concentration is :

or,  

=  

so, the change of 1 : 1/0.5

or, 1: 2

thus it will decrease by 50%.

or, as per the given options it will decrease by 11-50%

you need to have a picture of the atom that way we can answer it