Actual question from source:-
A 3.96x10-4 M solution of compound A exhibited an absorbance of 0.624 at 238 nm in a 1.000 cm cuvette. A blank had an absorbance of 0.029. The absorbance of an unknown solution of compound A was 0.375. Find the concentration of A in the unknown.
Answer:
Molar absorptivity of compound A = 
Explanation:
According to the Lambert's Beer law:-
Where, A is the absorbance
l is the path length
is the molar absorptivity
c is the concentration.
Given that:-
c = 
Path length = 1.000 cm
Absorbance observed = 0.624
Absorbance blank = 0.029
A = 0.624 - 0.029 = 0.595
So, applying the values in the Lambert Beer's law as shown below:-

<u>Molar absorptivity of compound A =
</u>
Answer:
This is what they are: An ion is a charged atom or molecule. It is charged because the number of electrons do not equal the number of protons in the atom or molecule. An atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.
This is their purpose: Once they reach our bloodstream, negative ions are believed to produce biochemical reactions that increase levels of the mood chemical serotonin, helping to alleviate depression, relieve stress, and boost our daytime energy.
Explanation:
Which ancient Greek philosopher was the focus of study for the Italian humanists?
ANS : Aristotle
Karst topography can cause drinking water to become more polluted
Answer:
205K
Explanation:
The following were obtained from the question:
n = 4moles
P = 5.6atm
V = 12L
R = 0.082atm.L/Kmol
T =?
PV = nRT
T = PV/nR
T = (5.6 x 12)/ (4 x 0.082)
T = 205K