Indicate whether the following statements are True or False: ___ 1. The maximum
ID: 517681 • Letter: I
Question
Indicate whether the following statements are True or False: ___ 1. The maximum region of absorption of a compound can be determined by measuring the absorption value of a solution of the compound over a range of wavelengths. ___ 2. When measuring the absorption of a compound in a solution, a sample of the solvent is "blanked out" in order to achieve an accurate measurement associated with the compound of interest. ___ 3. A linear relationship of absorption occurs at a fixed wavelength when measuring a series of concentrations of the solute. ___ 4. Water does not absorb light. ___ 5. An acceptable expression of Beer's Law is: Absorbance A = k c, where c is concentration. Calculate the concentration of NiCl_2 when 2.0 mL of water and 2.0 mL of a 0.390 M NiCl_2 solution are mixed together. Assuming the k values for absorptivity is 2.20 A/M, what is the concentration of the solution that gives an absorption of 0.429.Explanation / Answer
Part 1). True/false statement
1 : True
2 : True
3 : False
4 : True
5 : True
Part 2). concentration
concentration of NiCl2 = 0.390 M x 2 ml/4 ml
= 0.195 M
Part 3) concentration = Absorbance/k
with,
k = 2.20 A/M
we get,
concentration = 0.429/2.20
= 0.195 M