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Viscosity refers to the 'thickness' of a fluid as well as its resistance to shear and tensile stresses.

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How to drain engine oil by understanding oil viscocity issues

I asked this on the stackexchange automotive site but didn't get much response perhaps because it entails some chemistry knowledge. I could have asked without mentioning the automotive details however ...
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35 views

Are there any fluids which are both viscous and volatile? [closed]

I'm looking for a viscous fluid which will evaporate (completely) rather quickly. If propylene glycol evaporated like acetone, that would be the dream ticket, but neither the viscosity nor the ...
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Will PAEK polymers hydrolyze in concentrated sulfuric acid?

One of my duties at the company where I work is to perform intrinsic viscosity (IV) experiments on PAEK (poly(arly ether ketone)) polymers. These polymers don't dissolve well in most solvents, so the ...
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40 views

Are viscoelastic materials to be considered solids or fluids?

I recently stumbled upon the concept of viscoelasticity. Not being a chemist, but being interested in the topic, I started to read the wikipedia article. The main thing I extracted from it is: ...
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Is it possible to make synthetic oil without fossil fuel? [duplicate]

If human ran out of crude oil and all other fossil fuel, are we still able to create synthetic oil? I've searched online about the raw material of synthetic oil, but I'm still not sure if none of the ...
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198 views

Ethanol Water mixture viscosity

It is found that increasing composition of $Ethanol$ in $Ethanol$-$water$ mixture increases the viscosity of the mixture upto certain composition, but after that the viscosity begins to decrease again....
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Near melting thermoplastic material accumulates in the sharper corners. What is this phenomenon?

I have a part made of a thermoplastic material. When I heat it up and cool it down, the dimension of the part changes non-uniformly. Somehow the melted material tries to fill the sharper corners. So ...
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44 views

Are there any dielectric fluids that have low viscosity, high specific heat capacity, are safe, non-reactive, and are relatively cheap?

I am looking for a dielectric fluid that fits the following conditions: Non-conductive (dielectric): Resistivity greater than $\pu{1 x 10^6 Ω*m}$ (or a conductivity less than $\pu{1 x 10^-7 S/m}$). ...
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2k views

What is viscosity in terms of chemistry?

In physics, viscosity is the force applied in a unit area times time or basically Pascal times second. We could say that it is a measure of its resistance to gradual deformation by shear stress or ...
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What chemical should I use to thin UV cure epoxy?

The epoxy that I am working with is UV curable with a cycloaliphatic epoxy resin base. I am trying to reduce the viscosity. Whatever I add to thin the epoxy, it needs to be able to evaporate off so ...
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137 views

Alkali metals and viscosity

I've recently conducted a viscosity experiment to find the relationship between alkali metal ions, the concetration of the solution, and the viscosity of the solution. We used the Oswald viscometer to ...
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Why does viscosity decrease when divalent cations are dissolved into aqueous solutions of sodium carboxymethylcellulose?

Sodium Carboxymethylcellulose (CMC/NaCMC/Aqualon) is a common product used in many instances for its unique properties, especially its ability to make solutions viscous. It is well known that the ...
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Pressure increase due to the reaction of CaO and HNO3

Currently I'm facing difficulties in determining the pressure increase due to the reaction between $\ce{CaO}$ and $\ce{HNO3}$. To be more specific, we first fill a vessel with $\ce{H2O}$ and $\ce{CaO}$...
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Increase in Viscocity in Gases with Temperature

Why does viscocity increase with temperature in gases? When they gain kinetic energy, they should be more free right?
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Why is sugar syrup so sticky?

On the festival of Diwali, Indians exchange sweets and share their love. I did just that this very morning, but things don't always go the right way. I dropped a box of sweets and the sugary syrup ...
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Viscosity. Liquids and Solids?

Viscosity is defined as a measure of resistance to flow which arises dues to internal friction between layers of fluid as they slip past one another while liquid flows. MY ARGUEMENT\QUESTION: Why can'...
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410 views

Is there an all-natural, non-volatile and low viscosity oil?

The goal is to thin a vegetable oil so that it spreads easily on top of water. It is not for consumption and the flash point of the mixture should be >=95° Celsius". Vegetable oils tend to have flash ...
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3k views

Viscosity of branched vs. linear short alkanes

I was looking through the CRC Handbook of Chemistry and Physics section on liquid viscosities, trying to explain trends in viscosities. In higher alkanes, the viscosity increases with the degree of ...
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525 views

Correlation between functional group and viscosity of an organic compound?

I'm looking to explore the correlation between the type of functional group on an organic molecule and the viscosity of the compound. I know that viscosity is affected by intermolecular forces (Ion-...
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Why is mercury's surface tension so high, when its viscosity is low?

At a basic level, both surface tension and viscosity are the result of forces between particles. Usually we'd talk about intermolecular forces, because liquids are usually molecules, but obviously ...
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High Viscosity of Noble Gases

Why are the viscosities of noble gases higher than almost all other gases? This seems counter-intuitive since they have much weaker inter-molecular interactions and lower boiling points. Gas ...
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2k views

What is meant by viscous liquid?

I think all the liquids are viscous. So I was wondering what is meant by a viscous liquid as it is written in the first line of page on Oil at Wikipedia. An oil is any neutral, nonpolar chemical ...
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4k views

Why is honey more viscous than water?

Why is honey more viscous than water? And, if we boil honey to just below its boiling point, will it become equally viscous as water at normal temperature? How does changing temperature affect ...
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Flow cup viscometer vs rotational viscometer: limitations and use cases for each

What are the limitations of an inexpensive flow cup viscometer (or any other manual test viscometer) when compared to an expensive digital rotational viscometer?
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ASTM Viscosity Index Formula/Table derivation

How was the ASTM formula for Viscosity Index derived? Specifically with reference to the reference oils considered and the table for it. The viscosity index can be calculated using the following ...
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What are the fundamental parameter by which lubricants are graded?

I am into hobby machining using an old beaten CNC mill in my garage. Being novice my confidence is rather low and I have genuine fear of breaking something (even ancient CNC machines like mine cost a ...
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673 views

Relation between Temperature and viscosity of Linseed Oil?

I have been trying to get a relationship formula to determine the viscosity of Linseed oil. I have Absolute viscosity of the oil at 33.1 Cp (Source: http://www.engineeringtoolbox.com/absolute-...
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What is the viscosity of menstruation blood?

I am writing my bachelor thesis about alternative materials for feminine hygiene products and for testing I need to know what the viscosity is of menstruation blood. Can I use water as replacement for ...
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Are there any STP liquids not containing large amounts of hydrogen and oxygen that are safe for human contact?

I'm working on a science fiction short story and was wondering if there were any liquids that would be safe to bathe in while traveling on a space craft with artificial (spin-based) gravity. In such ...
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141 views

Can I change viscosity of an HDPE polymer?

I want to make composite with HDPE and wood, but when I melt it I have problem to mix them, because this polymer have high viscosity.
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Non-wetting fluids for precise volume measurements

I need to precisely measure the internal volume of an open steel fixture. I was planning to do this via displacement, but I'm wondering what the best fluid would be. Ideally it should have no ...
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4k views

Calculating collision diameter with viscosity, but not having the mass given

I've got a homework question i'm stumped on. The viscosity of the ethylene gas was measured at $99.8\times10^{-7}\ \mathrm{N\ s\ m^{-2}}$ at $288\ \mathrm K$. Calculate the collision diameter in $\...
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Effect of water viscosity (increased due to NaCl concentration) on dissolution rate of CO2

We did an experiment involving different $\ce{NaCl}$ concentration(ranging, 1-4%) on 100 mL of water. Our aim of the experiment was to find the dissolution rate of $\ce{CO2}$in the brine solvent. We ...
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Why doesn't the viscosity of water change much with temperature like it does for other substances?

I would like to know why water doesn't ever become like syrup before it freezes when many other liquids, such as hydrocarbons, seem to have a more gradual change from becoming more viscous and then ...
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How can I reduce Crystallization temperature of seed oil to be used in winter as biodiesel?

How can I reduce Crystallisation temperature of seed oil to be used in winter as biodiesel? The glycerol has been removed from the oil, and white spirit is used to reduce its viscosity.
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171 views

Could micrograms of polonium really change the viscosity of a whole teapot?

I was reading How radioactive poison became the assassin’s weapon of choice and it opens describing how The men eventually left, and Andrade cleared the table. As he poured the remaining tea away, ...
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138 views

Viscosity of two different solutions

Suppose that I have 10 kg of plastic/polymer that is non solvable in water. I then divide the plastic/polymer into two equal parts. Let us name the parts A and B in order to identify them. I then ...
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Polymer Slurry used in boring foundation holes?

I watched a video on the construction of Burj Khalifa, Dubai. The construction engineers answered that they're using a special type of protection known as Cathodic protection to protect from the ...