Plz asap
potassium (k), an alkali metal, and magnesium (mg), an alkaline earth metal, both combine readily with bromine (br), a halogen. what compound will each element (k and mg) most likely form with bromine?
a. kbr and mg 2br
b. kbr and mgbr
c. k 2br and mg 2br
d. kbr and mgbr 2

D. KBr and MgBr₂

Explanation:

The valence of potassium and bromine is 1, and the valence of magnesium is 2

Mg+Br₂=MgBr₂

2K+Br₂=2KBr

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%