Questions tagged [mixtures]
Questions related to the physical combination of two or more substances on which the identities are retained and are mixed in the form of solutions, suspensions, and colloids.
182
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What is the entropy of mixing of two ideal gases starting out with different pressures?
The entropy of mixing of ideal gas is given by this equation:
$\Delta S_{mix} = -nR(x_1\ln x_1 + x_2\ln x_2)$
Does this equation works only when the initial conditions of both compartments are at ...
1
vote
1answer
59 views
Find the molarity and molality
We take 10mL of $H_2SO_4$ with a $96\%$ of mass and density $1.84g/cm^3$, and we add it into a flask that has $0.5L$ of capacity, filled up to half of the flask with distilled water. We shake the ...
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0answers
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Are there any “tricks” to mixing two liquids with a magnetic stirrer?
I have two liquids - one that's mostly nonpolar, the other that's mostly polar. I'm trying to get a good mix between the two using a magnetic stirrer. One of the liquids is practically clear, so it's ...
1
vote
1answer
54 views
Find the molality
Find the molality of a mixture formed by mixing $200cm^3$ of $HNO_3$ that has a $69\%$ of richness and density $1.41g/mL$, with $1L$ of the same acid with $1.2M$ and density $1.06g/mL$.
Attempt. The ...
0
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0answers
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Dynamic viscosity of gas mixture (appropriate estimation)
What estimation of the dynamic viscosity $\eta = f(T)$ $([\eta] = \pu{Pa·s})$ of the gas mixture components would you recommend during adsorption at a low temperature, approx. $\pu{293 K}$ to $\pu{333 ...
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0answers
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Isolation of codeine phosphate from Tylenol 2
So here is my question. This may be controversial for some, but I would like to tell you it is purely speculative and has no bearing on anything I would actually do.
If one has in their hands a ...
1
vote
1answer
110 views
Calculating the percentage of (+)-2- butanol in the sample
Specific rotation of (+)-2-butanol is 12.5$^{\circ}$ . A sample of 2-butanol containing both the
enantiomers was found to have specific rotation value of –2.8$^{\circ}$ . What is the percentage of (+)-...
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votes
1answer
88 views
Green stuff from natural crystal [closed]
I continuously soak this natural quartz (it is originally white) in basin of water and salt, it has a metal on it too.
What caused the green stuff?
How to remove it?
2
votes
1answer
152 views
Is the negative excess volume of ethanol/water the cause of my math error?
I have a binary mixture, say ethanol at $90\%wt$ ethanol, $10\%wt$ water. According to Perry's Chemical Engineers' Handbook 9th Ed., that mixture has a density of $0.81797g/cc$ (at $20^{\circ}C$). ...
14
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3answers
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Is it possible to boil a liquid by just mixing many immiscible liquids together?
In open air, when vapour pressure reaches 1 atm, boiling takes place.
I read that if we add two immiscible liquids together, the total vapour pressure of the 'mixture' is close to $p = p^*_A + p^*_b$,...
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0answers
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Is it easier to mix a solution that is in the liquid or in the vapor phase?
In the article on dilution, Wikipedia has the following statement:
The same direct relationship applies to gases and vapors diluted in air for example. Although, thorough mixing of gases and vapors ...
0
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2answers
57 views
Are all mixtures linear?
I'm writing a computer program to help a factory produce bottles of mixtures. A mixture is usually alcohol, water and some other stuff, like menthol. But could also be water and NaOH and some oils (...
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1answer
225 views
Would Oxygen Gas and Ozone be a pure substance together? [closed]
If I have oxygen gas and ozone ($\ce{O2 + O3}$) together would it be considered a pure substance or a mixture?
And would pure substances always have the same molecular structure?
3
votes
2answers
396 views
Does Uranium ore count as a mixture?
I'm doing an assignment where we must research the separation of a mixture to obtain a useful final product. I thought about the separation of uranium from its ore after it has been mined, but I did ...
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1answer
37 views
Reason for nomenclature of azeotropic mixtures [closed]
The book states the solution which shows large positive deviation from Raoult's Law form minimum boiling azeotrope
What is meant by " minimum boiling azeotrope" or I should say what does ...
6
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2answers
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Reactions between enantiomers in a racemic mixture
As a follow up to this question I started thinking about another question. During racemization, enantiomers are mixed in a equal ratios to form an optically inactive mixture.
What type of reactions ...
0
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0answers
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What would happen if equal parts of hydrochloric acid, mercury and methylene chloride were mixed?
I was going through the archive of Real Life Comics (first time reader, enjoying it so far), and in one of the comics, the main character of the comic reveals he has ordered hydrochloric acid, ...
2
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1answer
12k views
How to calculate the vapour density of a mixture?
I have a gaseous mixture of $\ce{H2}$ and $\ce{CO2}$ which contains $66\%$ by mass of $\ce{CO2}$. I have to figure out the vapour density of the mixture (defined as mass of a certain volume of a ...
0
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0answers
29 views
Why does a dilution refrigerator work?
I read the wiki
https://en.wikipedia.org/wiki/Dilution_refrigerator
And my interpretation is that you get one cold liquid(helium 3) and add it to another (helium 4). The molecules of the liquids ...
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votes
2answers
76 views
Finding the pH of the resultant solution when a pH1 solution mixed with a pH2 solution [closed]
I want to know that is it possible that a $\mathrm{pH_1}$ solution mixed with a $\mathrm{pH_2}$ solution and the mixture would be less than $\mathrm{pH_1}$?
Is it possible that the result has a lower $...
Mathew Mahindaratne
26.7k15 gold badges34 silver badges68 bronze badges
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2answers
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Does ethylene glycol sink in water?
I’m a little concerned that there is a far stronger mix of antifreeze in my car's coolant system than I am aware. I check the antifreeze level in my car (using a refractometer) when the engine is cold ...
7
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1answer
509 views
Is the density of a two-component mixture always between the densities of its individual components?
There exist eutectic mixtures, in which the freezing point of the mixture is below those of either component of the mixture, i.e., the freezing point of the mixture is not intermediate between that of ...
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1answer
104 views
Mass percent and mole percent of a composition
The Problem
A gas mixture contains hydrogen, carbon monoxide, and carbon dioxide. Calculate:
a) The mass% hydrogen if the mixture contains 15 mol% $\ce{CO}$ and no $\ce{CO2}$;
b) The molar composition ...
0
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1answer
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How do I calculate the humidity inside sealed containers containing mixing salts?
At $\pu{25 ^\circ C}$:
saturated Magnesium chloride $\ce{MgCl2}$ keeps humidity 33% inside sealed containers.
saturated Sodium chloride $\ce{NaCl}$ keeps humidity 75% inside sealed containers.
I ...
0
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1answer
25 views
Hydrogen peroxide and ThickenUp (potassium chroride) [closed]
Retr0bright is used to whiten yellow plastic.
The original recipe contains xantham rubber that is a bit hard to find.
I'm thinking about using Nestlé ThickenUp that contains xantham rubber, but it ...
4
votes
2answers
435 views
What is the entropy of mixing a gas into the whole atmosphere?
Suppose I release 1 mole of pure argon into the atmosphere. What is the entropy of mixing? The equations I have found seem to only apply to the case of a fixed volume. Should I use an estimate of the ...
3
votes
2answers
237 views
Calculating the dissociation constant of one acid in a mixture
A solution contains $\pu{0.09 M}~\ce{HCl}, \pu{0.09 M}~\ce{CHCl2COOH}$ and $\pu{0.1 M}~\ce{CH3COOH}$. The $\mathrm{pH}$ of the solution is $1$. Given that the $K_\mathrm{a}$ of acetic acid is $10^{-5}$...
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0answers
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Energy and impurities balance for adsorption with a fixed bed (with description)?
Do you have any suggestion where to look for a source of information about energy and impurities (component) balance for adsorption of mixture CO2/H2O in fixed bed?
I have looked into many articles /...
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1answer
56 views
Difference between homogeneous and heterogeneous mixture [closed]
When i mix two equal but large number of stones it is possible (though extremely unlikely) that stone a and stone b perfectly segregate themselves into two halves or that they are uniformly ...
0
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0answers
59 views
Gas / Gas mixture dynamic viscosity temperature and pressure dependance
I’m trying to get an accurate interpretation of certain gases ($CO_2$, $N_2$, $NO$, etc.) dynamic viscosity [Pa.s] as a function of temperature and pressure (afterwards determine the dynamic viscosity ...
1
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1answer
133 views
Did I accidentally create phosgene gas [closed]
I accidentally mixed bleach and acetone trying to remove hair dye stains from my shower wall. The mixture turned orange when the bleach and acetone touched. Could I have created phosgene gas ...
4
votes
1answer
33 views
Combination of polydisperse polymer mixtures
Say I'm given a mixture of batches of polydisperse polymers. I know the weight $w$, the number average $ \bar M_n$, and the weight average $ \bar M_w$ of each batch that was added to the final mixture....
3
votes
3answers
441 views
What does my textbook mean by saying this about petroleum?
It reads:
Petroleum consists of crude oil and natural gas and contains a mixture of up to 300 hydrocarbons, including sulfur and nitrogen compounds. It is formed over thousands of years from the ...
4
votes
1answer
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Miscibility of Hexane and Ethanol (Anhydrous vs 96%)
In my lab, I mixed 8:2 (mass:mass) of Hexane:Ethanol
(Hexane: 0 ppm of water content, ...
Mathew Mahindaratne
26.7k15 gold badges34 silver badges68 bronze badges
5
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1answer
1k views
Strong exothermic mixing of two 'safe' liquids
I have read (thanks to Stack Exchange) that mixing water and sulfuric acid is exothermic, as is NaOH and HCl.
Are there two 'safe' liquids that can be mixed and produce anywhere near the same amount ...
14
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1answer
724 views
Mixing two containers of each water and ethanol to varying degrees of purity
In the following question, the water/wine mixing problem was recast in chemical terms. However, partial molar volumes can make this a much more challenging problem than it appears on the surface.
...
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2answers
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How to calculate the partial pressure of oxygen in this mixture of oxygen and argon?
A $\pu{19.3 g}$ mixture of oxygen and argon is found to occupy a volume of $\pu{16.2 L}$ when measured at $\pu{675.9 mmHg}$ and $\pu{43.4 ^\circ{}C}$. What is the partial pressure of oxygen in this ...
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1answer
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Most efficient way to purify household vinegar: distillation or freezing?
I am aware that there are better ways to purify acetic acid out of a water-acid mixture than these, but which one out of distillation (using heat) and fractional freezing (using cold) would gain a ...
0
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0answers
37 views
What is the result of the combustion of the mixture?
I prepared a little experiment about solid rocket propulsion. I have used water ($H_{2}O$), potassium nitrate ($KNO_{3}$) and saccharose ($C_{12}H_{22}O_{11}$).
I made the mixture in a pan by cooking ...
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0answers
156 views
Calculating concentration of a powder in a liquid
I'm trying to determine how to calculate proper measurements for a 5% concentration of a vitamin C ester powder (ascorbyl palmitate) mixed in a 50/50 carrier oil mixture (jojoba oil/squalane oil) with ...
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2answers
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Why is water considered a pure substance instead of a mixture?
Why is water considered a pure substance instead of a mixture?
Wouldn't it, when the hydrogen atoms combine with the oxygen atom, be considered a mixture, because the atoms were combined to form a ...
0
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1answer
43 views
How to find the volume of the products in methane combustion?
The combustion of methane gas, $\ce{CH4}$, gives as products $\ce{CO2}$ and $\ce{H2O}$, both in the gas phase. If $1$ liter of methane is burned in the presence of $10$ liters of $\ce{O2}$. Suppose ...
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0answers
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Why Does Adding Catalyst Slow Down My Reaction?
I currently did a lab where I was meant to identify factors that increase the rate of the reaction. I reacted Glucose with Potassium Permanganate and used Sulfuric Acid as a catalyst. But in my ...
0
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1answer
544 views
dissolving powder [closed]
I have small amount of rosemary herb powder mixed in a cup of water and it's only party dissolving. I was wondering if there is another powder that can be added to this water solution and dissolve the ...
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0answers
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Combining two high-VP chemicals to get a low-VP mixture
I'd like to do a class experiment as a metaphor for human relationships. Two people each have a different chemical which evaporates quickly (at STP). There is one glass between them. If only one ...
0
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1answer
92 views
Why does adding salt to water help distillation?
I've been looking at instructions on how to get lanolin from fleece and a lot of the instructions mention that adding salt to the water before distillation will increase the lanolin yield. Why is this?...
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2answers
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Ratio of Water to Isopropyl Alcohol? [closed]
I am looking for a very simple formula to calculate the ratio of water to 99% isopropyl alcohol that I need to prepare a solution with a density of 0.925 g/cm3. I am assuming there is one.
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0answers
34 views
Carbon Capture Absorption with Henry's Law
Assume the Henry’s coefficient for water at $\pu{20 °C}$ is $\pu{1.6E8 Pa}.$ What is the mole fraction of $\ce{CO2}$ that will be dissolved in water assuming that it is at equilibrium with a flue gas ...
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0answers
33 views
Gelifying hydrogen peroxide
What substances could be used to gelify 60% hydrogen peroxide? I imagine anything organic like agar would be broken down by the radicals. I tried looking up what dentists use and the only thing that ...
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0answers
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Mixing ink with alcohol, MEG and water
First of all, I'm not a chemist and my knowledge in chemistry is not that extensive. However, I would like ask the following question: are there any chemical reasons that would explain that mixing a ...
