Answer:
0.21 M
Explanation:
The method to solve this question is to use Beer´s law which is expressed by
A = εcl
where A is the absorbance, ε is molar absorptivity ( M⁻¹·cm⁻¹ ), c is the concentration M (mol/L), and l is the path length in cm.
Solving for c in the above equation
c = A / εl = 0.458 / ( 2.16 M⁻¹·cm⁻¹ x 1.01 cm ) =0.21 M
Note: there is an error in the units for the absorptivity constant, it should have said M⁻¹·cm⁻¹ . You can check this by realizing the absorbance is unitless and when we multiply M⁻¹·cm⁻¹ with the units of concentration c (M) and path length (cm ) the units cancel.
