To calculate the pKa of the weak acid, we use the Henderson-Hasselbalch equation. It is expressed as pH = pKa - log [HA]/[A-]. This equation takes into account the concentration of the substance that does not dissociates into ions since it is a weak acid. We caculate as follows:
pH = pKa - log [HA]/[A-]
9 = pKa - log 1/100
pKa = 7
Answer:
carbon dioxide concentration goes down, temperature goes down. Carbon dioxide goes up temp goes up, carbon dioxide is directly related to temperature by insulating it in the earths atmosphere and if there's less of it then the temp would go down.
Explanation:
4.1 h = 14760 s
<span>t 1/2 = ln 2 / k </span>
<span>k = rate reaction = 4.97 x 10^-5 </span>
<span>ln 0.045 / 0.36 = - 4.97 x 10^-5 t </span>
<span>2.08 = 4.97 x 10^-5 t </span>
<span>t = 41839.9 s = 11 h 37 min 19 s</span>
The percentage of Chromium in Chromium Oxide is calculated as follow,
Step 1: Calculate Molar mass of Cr₂O₃,
Cr = 51.99 u
O = 16 u
So,
2(51.99) + 3(16) = 103.98 + 48 = 151.98 u
Step 2: Secondly divide molar mass of only chromium with total mass of Cr₂O₃ and multiply with 100.
i.e.
=

× 100
=
68.41 %
So, the %age composition of chromium in chromium oxide is
68.41 %.