All Questions
6
questions
5
votes
2
answers
3k
views
Why does the dissolution of calcium hydroxide have a negative entropy?
We had an experiment on the dissolution of calcium hydroxide and we obtained the experimental entropy value $\pu{-203 J mol^-1 K^-1}$ with a percent error of $26.7\%.$ Doesn't dissolving a solid in a ...
2
votes
0
answers
36
views
Why isn't the chemistry of a zinc-air battery (meaningfully) hindered by an activation energy barrier?
Virtually every source I've read pertaining to zinc-air batteries explain the chemistry of it either using these formulae or a simplified version of them:
$$
\begin{align}
&\text{Anode:} &\...
- 139
3
votes
4
answers
2k
views
Calculation of Degree of Dissociation from Ostwald's Dilution Law
A "weak" electrolyte, $\ce{A+B-}$, ionizes in solution as:
$$\ce{AB <=> A+ + B-}\tag{1}$$
$$ K_d =\dfrac{\ce{[A+][B-]}}{\ce{[AB]}}=\dfrac{(\alpha c_{0})(\alpha c_{0})}{(1-\alpha )c_{0}}=\...
- 333
1
vote
1
answer
77
views
Seeing solubility in various cases
Match the following:
$\begin{array}{|c|c|c|c|} \hline &\textrm{Column-I}&&\textrm{Column-II} \\\hline \textrm{(A)}&\ce{AgBr}&\mathrm{(p)}&\mathrm{(Solubility~in~water~is~more~...
- 111
0
votes
0
answers
29
views
How to account for the common ion effect on osmolarity quantitatively?
In adjusting the osmolarity of a solution of Benzalknonium Cl, Disodium Editate, and Disodium borate/boric acid buffer to be isotonic (about 290 mOsm), the addition of NaCl showed unexpected behavior, ...
- 497
2
votes
2
answers
148
views
Ionic equilibrium between multiple ions
This is a question from IIT-JEE 1993:
For the reaction
$$\ce{[Ag(CN)2]^- -> Ag^+ + 2CN^-}$$
the equilibrium constant at $\pu{298 K}$ is $\pu{4e-10}$. The silver ion concentration in a ...
