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4 votes
0 answers
86 views

Notation for spectral density in experimental community

In an open quantum system setup where the system is coupled to infinite harmonic oscillators as bath (as in the Caldeira leggett model, for example), through the Hamiltonian, $$H = \frac{\hat{p}^2}{2m}...
Prem's user avatar
  • 91
-2 votes
1 answer
397 views

Notation for inclusion of water in a dissolution equation

Earlier I had a student come by wanting to know how to show the dissolution of $\ce{NH4OH}$ in water. I would think we would just write it: $$\ce{NH4OH(aq) <=> NH3(aq) + H2O(l)}$$ I say this as $...
neurosciencecalc's user avatar
3 votes
1 answer
213 views

What is the difference between these two formulas for pH of weak acids?

In the German Wikipedia article on $\mathrm{pH}$, I found the following formula for calculating the $\mathrm{pH}$ of weak acids (which are there defined of having $4.5 < \mathrm{p}K_\mathrm{a} < ...
jng224's user avatar
  • 273
0 votes
1 answer
5k views

Meaning of mass concentration "units" % m/v [closed]

In a saline solution that is 5.750% (m/v) potassium iodide $(\ce{KI}),$ there are: a) 5.750 mL $\ce{KI}$ per 100.0 mL $\ce{H2O}$ b) 575.0 mg $\ce{KI}$ per 10.00 mL of $\ce{KI}$ solution c) 5.750 g $\...
욕��Desi's user avatar
0 votes
2 answers
208 views

Why do we use [H⁺] and [OH⁻] in balancing redox reactions instead of using [H₃O⁺] and [OH⁻]? [duplicate]

For what reason is it universally agreed upon that we use $$\ce{H+ + OH-}$$ ions in balancing water on either side of the reaction, but not the $$\ce{H3O+}$$ ions?
user243851's user avatar
0 votes
1 answer
2k views

Should moderately soluble compounds like calcium hydroxide be denoted (aq) or (s)?

I'm learning to write balanced molecular and ionic equations. For "moderately soluble" compounds such as calcium hydroxide, how do I know whether to write the state symbol as (aq) or (s)? This is the ...
Mareim's user avatar
  • 65
4 votes
1 answer
4k views

Notation "5% solution"

What does 5% aqueous solution of glucose mean? Note that it's just 5% and not 5%w/w. Do we assume it to be w/w? The question is If the osmotic pressure of 5% aqueous soultion of glucose is $\pi_1$ ...
user80551's user avatar
  • 400