# Questions tagged [solutions]

This tag should be applied to questions dealing with solutions of any kind. A solution is a liquid or solid phase containing more than one substance where, for convenience, one (or more) substance(s) called the solvent is treated differently from the other substances, which are called solutes. If water is the solvent, then the more appropriate 'aqueous-solution' tag should (also) be specified.

622 questions
1k views

### Unit conversion of Molar Conductivity

I know this might be a silly question but I am confused with different answers of internet. My question is: Molar conductivity is given as: Molar conductivity = $k÷M$. SI unit of : k is S/m & ...
80 views

### If some particles of liquid in a solution convert to vapour then why can't some liquid particles convert to solid?

I was reading about the vaporisation of liquid when I came across the following statement. The average energy of the particles in a liquid is governed by the temperature. The higher the ...
376 views

### Extract ammonium sulfate from water

What is the best method to extract ammoniumsulfate from water? The assignment is as follows: Manure is being processed and the product left is a mixture between water and ammonium sulfate, ...
869 views

### How many grams of CuSO4*5H2O yield 10 grams of H2O?

If I want there to be 10.00 g of water in the copper (II) sulphate pentahydrate sample that I'm measuring, what mass of the substance will I need in order to have 10.00 g of water? I solved this ...
2k views

### Differences between miscible and soluble

What are the differences between soluble and miscible? So far I found this (page 3 http://faculty.sites.uci.edu/chem1l/files/2011/03/D01MANmiscibility.pdf): soluble=solid dissolves into a liquid ...
73 views

### Removing potassium chloride crystals from a mineral composed of manganese dioxides

How can I remove crystals of potassium chloride from a mineral composed of manganese dioxides? Hey, i'm a high school student trying to do a good cryptomelane sample to use in my scientific project. ...
404 views

### How to dissolve cat hair without effecting fabric?

I am wondering if it is possible to create some sort of a solution that will dissolve cat hair (or dog hair), but, is not harmful to the surrounding fabric? I am picturing a solution you would soak a ...
791 views

### Why is finding [H+] when given [OH-]= 3.57e-5 M wrong when I use -log[OH-]?

Question/Problem I know that [H+][OH-]=$10^{-14}$ And the problem asks to find out the concentration of H+ when the concentration of OH- is $3.57*10^{-5}$M By using the equation above i find that ...
119 views

### Negative ions affecting galvanic cell voltage

I don't see why negative ions don't affect the voltage. I mean the electric field of a negative ion like $\ce{SO4^{-2}}$ is not like what $\ce{NO3-}$ produces that means that it should affect the ...
93 views

### organic hard surf wax?

I made some organic surf wax with 4 parts beeswax and 1 part coconut oil. The wax turned out to be sticky but had no tack. I'd like to make wax for warm water that forms a layer of hard bumps on the ...
198 views

### how are colloids and suspensions solutions?

my definition of solution is a homogenous mixture of a solute and solvent. and in my textbook they call colloids and suspensions solutions . how is this possible if both of them are heterogenous ...
3k views

### A drop of water in a tin of sugar: Which one's the solvent, the sugar or the water?

The other day, when we were dealing with the chapter Solutions, our teacher asked us this: If I add a drop of water, to a tin full of sugar (without mixing it in), what's the solvent here? The ...
8k views

### Why do non-polar covalent compounds dissolve in non-polar covalent compounds only?

My textbook says that electrovalent and polar covalent compounds dissolve in electrovalent compounds and polar covalent compounds but not in non-polar covalent compounds. I understand the reason for ...
19k views

### How to determine which aqueous solution has the largest freezing point depression

Question This is more of a conceptual question. Let's say that we are given different aqueous solutions and we are asked to choose the one with the highest freezing point depression, which do we ...
35 views

### Diffused Layer ion in Electrix Double Layer

When KI is added to AgNO3 soln, so AgNO3 is in excess, collidal particle is AgI:Ag+ with diffused layer of I-, Why is the diffused layer not of NO3- when the anion in excess is NO3-? If we had KI in ...
413 views

### Finding the molarity of an acid in a titration

I was doing a question that asks the molarity of a 10 mL of tartaric acid that is titrated to phenolphthalein endpoint with 20 mL of 1.0 M NaOH. I worked it out by equating the molarity of the NaOH ...
2k views

### Boiling point elevation for a mixture of ethanol and water

Properties such as boiling point, freezing point and vapour pressure of a pure solvent change when solute molecules are added to get homogeneous solution. These are called colligative properties....
31 views

### Confusion over percentage volume

We've been told our lab report has to be written with "% v/v" instead of volume. I understand how to calculate it, however I'm unsure if I'm doing the right thing when it comes to using it later on. ...
159 views

### Chemical in (s) mixed with chemical in (aq) vs. chemical in (aq) mixed with chemical in (aq)

Hopefully the title is comprehensive enough. But I am wondering, does it make a difference if you take a powder and mix it with an aqueous solution or take a solution with the very same chemical ...
624 views

### Finding out pKa of acid from molar conductivity

I'm reading about the electrical properties of solution where there is a problem like that: The molar conductivity of $0.0250\ \mathrm M$ $\ce{HCOOH(aq)}$ is $4.61\ \mathrm{mS\ m^2\ mol^{-1}}$. ...
52 views

### Is it possible to supercool hydrated salts like magnesium nitrate hexahydrate supercool just like for sodium acetate trihydrate?

Recently I stumbled upon the phenomenon of supercooling. I know that you can do this with water as well as with some phase change materials, like sodium acetate trihydrate (from the wintersport ...
886 views

### Molarity of an ion

What is the molarity of sulfate ions in a 0.010 M of aqueous aluminum sulfate solution? Can someone explain this question for me. I know the compound is $\ce{Al2(SO4)3}$. Does that mean I just ...
147 views

### Why is the strong acid written in a net ionic equation? [closed]

Strong acids dissolve and break apart into ions, so in a net ionic equation, why are they written?
457 views

### How to measure concentrations using emission spectrum?

Imagine I am using emission spectroscopy to identify the presence of ions in a solution. Would it be possible to use the intensity of the spectrum to find the concentration of each ion in the ...
38 views

### Ionic emission spectrum contamination

Imagine that I am trying to identify the presence of ions from among the metals $\ce {Li,Na,K,Ca,Sr, Ba}$ in some solution through their emission spectrum. By mistake the wire used to introduce ...
63 views

### Any differences in metal ion emission spectra?

If I measure the emission spectra of potassium using the following solutions 1) $0.1~\mathrm{M}$ of $\ce{KNO3}$ 2) $0.1~\mathrm{M}$ of $\ce{K2SO4}$ will I see any significant differences? I think ...
789 views

### Find the standard Gibbs' free energy of formation at 298.15 K for O2 gas dissolved in the saturated aqueous solution?

The solubility of $O_2(g)$ in water at $25^o \text{C}$ and $\text{1 bar}$ pressure of $O_2(g)$ above the solution is $0.00126$ $mol$ $O_2(g)/kg$ $water$. Find $\Delta_fG_{298.15}^o(O_2(g),sln)$. I ...
191 views

### How to make a CCl3F Fluorine NMR standard?

I am running some fluorine NMR and would like to make a bulk solution of $\ce{CCl3F}$ in $\ce{CDCl3}$ to aid in assessing the amount of fluorinated product present by having my NMR solvent act as a ...
397 views

### Calculating the pH of buffer solution made of two salts of a polyprotic acid

When we are making a buffer solution by solutions of a weak acid and its salt like $\ce{CH3COOH}$ and $\ce{CH3COONa}$, or by a weak base and its salt like $\ce{NH3}$ and $\ce{NH4Cl}$, we can use the ...
408 views

### Interpreting the phase diagram of a minimum boiling azeotrope

Exactly what does the line AB signify in the above phase diagram? Also, why is the curve divided at the azeotropic point?