All Questions
12
questions
2
votes
4
answers
172
views
How can the Kw of water be constant?
I know in neutral solution, $\ce{[H+]}= \ce{[OH-]}= \pu{1.0 x 10^-7}$.
However, let’s say I add an acid like HCl. This will increase $\ce{[H+]}$, therefore it’s no longer $\pu{1.0 x 10^-7}$, but is ...
- 41
1
vote
0
answers
57
views
Can addition of a "neutral" salt like NaCl assist pH test strip measurement accuracy in low ionic strength/poorly buffered solutions?
After a web-search, it seems ISAs (Ionic Strength Adjusters) are offered commercially to assist pH electrode/probe measurements. Presumably meant to increase conductivity (without affecting pH ...
- 129
2
votes
1
answer
972
views
Creating a 10 ppb Lead Nitrate Solution
I’m trying to make a 10 ppb Lead Nitrate solution as part of a concentration calibration step for a Beer Lambert’s Law experiment. I plan on performing a dilution in three steps. The calculations have ...
- 467
-1
votes
1
answer
108
views
What formula allows adjusting balance of (Ethyl Alcohol / Water / Caffeine powder) to know concentration for the Caffeine solution?
I am experimenting with different levels of concentrated caffeine solution. The solution has a small percentage of ethyl alcohol, in the $\ce{H2O}$.
Problems encountered too much ethyl alcohol ...
- 45
1
vote
2
answers
448
views
Does adding solutes to water alter its triple point? [closed]
Does adding solutes to water alter its triple point? If yes, how do we find the new temperature and pressure of this point?
- 153
4
votes
1
answer
274
views
Why is Iron very rare in seawater compared to many other elements?
I don't know the associated technical words to research this question.
There was high presence of Iron in the oceans in anoxic precambrian times, and today copper is 5 times more abundant in the ...
- 573
9
votes
1
answer
4k
views
Why does Dead Sea water feel greasy?
The best explanation I found so far is this:
These salts (magnesium, potassium, sodium, etc.) are responsible for the "greasy" feel of the water.
But it doesn’t say which salts exactly are ...
- 201
3
votes
0
answers
1k
views
Calculating total volume mixing NaCl and water
I'm (as a non chemist) trying to calculate the the volume of a NaCl solution. The problem is that I know the volume of water prior to mixing in NaCl, but I want to know the volume of the solution ...
- 131
1
vote
1
answer
2k
views
How do hydrogen bonds break the ionic bonds of a crystal lattice? [duplicate]
In the case of water dissolving sodium chloride. I was under the impression that hydrogen bonds were much weaker than the ionic bonds in sodium chloride, so how do they overcome the ionic bond ...
- 51
19
votes
3
answers
60k
views
Why there is no change in water level when salt is added?
Let us say we have one glass of water and after that when we add one or two spoon of salt then we notice that salt dissolves in it but when we measure the water level we found that there is no ...
- 1,491
28
votes
5
answers
17k
views
Why is water "the universal" solvent?
This is an old question that our textbook tried to answer but worsened the situation.
Many things are soluble in water. So many, that studying solutions will always require studying aqueous ones. It ...
- 10.7k
7
votes
1
answer
2k
views
Why do some solid chemicals dissolve better in colder water?
I just discovered that some solid chemicals, such as $\ce{Na2SO4}$, dissolve better in cold water than hot water from here and would like to know if there is any particular reason as to why. Is it ...
- 173