A buffer solution is made using a weak acid, HA. If the pH of the buffer is 9 and the ratio of A– to HA is 100, what is the pKa
1 answer:
You might be interested in
Answer:
Here's what I get
Explanation:
(a) Intermediates
The three structures below represent one contributor to the resonance-stabilized intermediate, in which the lone pair electrons on the heteroatom are participating (the + charge on the heteroatoms do not show up very well).
(b) Relative Stabilities
The relative stabilities decrease in the order shown.
N is more basic than O, so NH₂ is the best electron donating group (EDG) and will best stabilize the positive charge in the ring. However, the lone pair electrons on the N in acetanilide are also involved in resonance with the carbonyl group, so they are not as available for stabilization of the ring.
(c) Relative reactivities
The relative reactivities would be
C₆H₅-NH₂ > C₆H₅-OCH₃ > C₆H₅-NHCOCH₃
Answer:
The absorbance of the myoglobin solution across a 1 cm path is 0.84.
Explanation:
Beer-Lambert's law :
Formula used :
where,
A = absorbance of solution
c = concentration of solution
= Molar absorption coefficient
l = path length
= incident light
= transmitted light
Given :
l = 1 cm, c = 1 mg/mL ,
Molar mass of myoglobin = 17.8 kDa = 17.8 kg/mol=17800 g/mol
(1 Da = 1 g/mol)
c = 1 mg /mL =
1 mg = 0.001 g, 1 mL = 0.001 L
The absorbance of the myoglobin solution across a 1 cm path is 0.84.