An aqueous solution contains two absorbing species, x and y. when a solution of this mixture is put into a 5.000 cm cell, the total absorbance of a mixture of x and y at 300 nm is 0.372, while at 250 nm it is 0.478. the individual molar absorptivities of x and y are as listed below. what are the individual concentrations of x and y in this mixture? 250 nm 300 nma. x 4.05 x 104 m-1 cm-1 3.22 x 104 m-1 cm-1b. y 3.76 x 104 m-1 cm-1 2.86 x 104 m-1 cm-1

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

the answer is b & c i believe : )

the answer is 303.15 or 303