A stock phenolphthalein solution was prepared by dissolving 0.050 g in a total volume of 100.0 ml. You place one drop (0.050 ml) of this stock solution into a flask and dilute to 100.0 ml. The measured absorbance of this diluted sample is 0.18. What is the value of molar absorptivity, ε?

the value of molar absorptivity is 229000

Explanation:

given data

phenol phthalein solution = 0.050 g

total volume = 100.0 ml

dilute = 100.0 ml

diluted sample = 0.18

solution

we get here concentration that is express as

concentration = ( mass of solute × 1000 ) ÷ ( molar mass of solute × volume of solution ) .............1

put here value

concentration =    

concentration = 0.00157 M

and here dillution equation is express as

c1 × v1 = c2 × v2   .................2

here c1 and c2 is initial and final concentration

and v1 and v2 is initial and final volume

put here value  

0.001571 × 0.050 = c2 × 100

c2 = 7.855 × M

and

now we get molar by absorbance equation that is

A = E × C ×  l   ................3

here A is absorbance and E is molar and c is absorptivity and l is path length

put here value

0.18 = E × 7.855 ×  × 1

E = 229000

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.

it is the most commonly accepted one