Look at the bottom of the periodic table. There are two rows of elements separated from the others. Where do these elements fit in the structure of the table? Use the atomic numbers to help you decide. Select the correct option from each drop-down menu to describe the location of these elements.

The first row of elements fits in period (6),(7),(8),(9), after the element (lanthanum (LA)),(radon (Rn)),(organesson(Og)),(beryllium (Be)). The second row of elements fits in period (6),(7),(8),(9), after the element (actinium (Ac)),(organesson(Og)),(radon (Rn)),(magnesium (Mg)).

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 just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year