Pls help I don’t understand at all

Mass = 12.48 g

Explanation:

Given data:

Mass of sulfur dioxide = 25.0 g

Mass of sulfur formed = ?

Solution:

Chemical equation:

SO₂      →        S   + O₂

Number of moles of SO₂:

Number of moles = mass/molar mass

Number of moles = 25.0 g / 64.07 g/mol

Number of moles = 0.39 mol

Now we will compare the moles of SO₂  with S.

                     SO₂        :          S

                        1          :           1

                       0.39     :         0.39

Mass of sulfur:

Mass = number of moles × molar mass

Mass = 0.39 mol × 32 g/mol

Mass = 12.48 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%

i'm pretty sure it is letter c.) car