Acalibration curve relating absorbance(y) to concentration (x, measured in mol/l) of y= 0.36x-0.011 use the calibration curve to determination of the concentration of a solution with an absorbance of 0.02.

The concentration is 0.025 M.

Explanation:

We will use beer law to find the concentration.

A = εmCl

This law relate to the linear equation Y = mx + b in following way,

A = y = absorbance

m = εm = slope or extinction coefficient in beer law.

x = c = concentration

and l is length which is 1 cm

Thus equation can be written as,

A = εmc + b

A - b / εm = c

in order to find the concentration we will abstract the intercept from absorbance and then divide it by the slop.

0.02 - 0.011 / 0.36 = c

c =0.009

c = 0.025 M.

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%