Questions tagged [materials]

Material is a general term for a chemical substance or a mixture of substances with certain, well defined physical properties.

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91
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8answers
51k views

Is toothpaste solid or liquid?

My teacher didn't answer this properly: Is toothpaste solid or liquid? You can't say toothpaste is a solid because solid material have a fixed shape but toothpaste doesn't. However, you can't say ...
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0answers
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1answer
60 views

What is the naming convention for Sn and Pb in inter-metallic compounds?

How would one go about naming inter-metallic (specifically, transition post-transition) compounds containing tin and lead? It is usually easy figuring out the naming of such compounds as they follow ...
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1answer
3k views

Length of copper wire in 1 lb spool

I was asked the following question in my introductory chemistry class: The diameter of metal wire is often referred to by its American wire gauge number. A 16-gauge wire has a diameter of $\pu{0....
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0answers
22 views

How to make a nanocellulose filter [closed]

Does anyone know where I can find a clear, simple method to make a nanocellulose filter? A link or diagram, with materials etc. would be appreciated. This is for a science project and I currently have ...
15
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2answers
2k views

Conception and manufacture of the Avogadro Project's (nearly) perfect silicon sphere (and, what is “atomic feeling”?)

The Avogadro Project, an effort prior to the recent redefinition of Avogadro's constant to design a nearly perfect sphere of silicon-28, apparently relied on the fine fingers of optician Achim ...
7
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1answer
741 views

What is the @ symbol used for in material science?

I came across the phrase "Silicone Rubber/Paraffin@Silicon Dioxide" also written as $\ce{SR/pa@SiO2}$, utilising the @ symbol. How can I understand what this means?...
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0answers
29 views

Semiconductor Li-ion batteries

I have recently come across the concept of semiconductor Li-ion batters, for instance carbonised polyacenic semiconductor (PAS) Li-doped materials. I am not sure how common it is for a battery to be ...
5
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2answers
489 views

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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1answer
24 views

Safe coating to make a 3D printed respirator mask airtight [closed]

What is a good example of something safe that could be applied as a coating layer to the walls of a 3D printed respirator mask to make them truly airtight (seal pores and fissures) while (ideally) ...
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0answers
58 views

Why does copper oxidise if it is considered a “noble metal”?

I'm an electrical engineer and not a chemist, so please excuse me if this is obvious. When soft-soldering electronic parts, we’re normally taught to clean copper of oxides (like using flux and so on) ...
2
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1answer
71 views

Replacement for optical calcite (Glan Thompson prism)?

I notice that Glan Thompson prisms seem to be the preferred optics for doing polarimetry and have been for at least 75 years. One instrument maker says that polaroid films can be used but they tend to ...
2
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0answers
53 views

Why upon melting of PEO between crossed polars colours appear?

Crystalline PEO when under crossed polars shows distinct Maltese cross pattern. Being birefringent, when polymer crystal align with the polarizer or analyser it shows extinction regions (effect known ...
7
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2answers
27k views

Why are so many ionic compounds brittle?

Even when ionic compounds are strong (e.g. rubies and sapphires), they are neither malleable nor ductile in the slightest, and if sufficient stress is put on them, they will shatter, not bend. Why is ...
4
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2answers
250 views

Material that is flexible when cold but becomes brittle when hot

I'm looking for a material that I can use to make a mesh netting. It should be flexible and have reasonable tensile strength when cold but brittle when hot (>$\pu{400^\circ F}$). I want to use it to ...
9
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2answers
2k views

Have we ever created artificial metals?

I really don't know anything about chemistry, but I was wondering about the following vague question: has any substance been created that does not contain any metallic elements, but is metallic? In ...
2
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0answers
18 views

Non-conducting substance with a glass transition temperature around 400 to 600 °C?

Am looking for a substance to seel two pieces of ceramic that will have molten plastics flowing between at 300+ °C however silver solder circuit traces inside the device prevent me from going much ...
0
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2answers
53 views

What is meant by a 'hydrophilic' sphere?

So, I know that a hydrophilic material is defined as those with a special affinity for water, opposite to hydrophobic, those that naturally repel water. I am investigating the impact of spheres with ...
1
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1answer
33 views

Can Ferrofluids vaporise to gaseous state and Condense back to liquid state and do it many times over? [closed]

Here is the Link for Ferrofluids for basic idea. After going through this Wiki link, probably many people will come to a conclusion like when Ferrofluid boils, its carrier liquid vaporises and nano ...
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2answers
298 views

Which method can be applied to separate ferrofluid liquid from oil?

I want to know if there is any substance, liquid or any other stuff to separate ferrofluid from oil after mixing them.
6
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1answer
115 views

Are there any molecular modeling programs that can build materials made up of three or more elements into a cylindrical shape?

I would like to build a material similar to what is in the image below. I have tried programs such as Material Studio, Quantum ATK, and VNL, but most of them can only do materials with 2 elements.
1
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1answer
677 views

Equation to find specific gravity (or density) from a solution of sugar and water

Is there an equation or simple way to calculate the final density of a solution made from x grams of sugar and y liters of water? And would it work in reverse? if we have y liters of water at z ...
3
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1answer
105 views

Products of silicate synthesis

I'm attempting to make a hard refractory cement to apply over kiln brick made of sodium silicate and Perlite. This creates a very good kiln brick, however they are susceptible to abrasion. I've been ...
2
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0answers
46 views

C60 Fullerene Polymers?

Upon scouring Wikipedia for info about fullerenes to research, I came across this paragraph in the page on Buckminsterfullerene (C60): Under high pressure and temperature, repeated [2+2] ...
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0answers
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What is the materials science behind thermal diffusion in multispectral camouflage?

I've been interested in infrared and near-infrared camouflage (called multispectral camouflage) for a couple of days now, and I've found a video or two of certain companies that have created fabrics ...
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1answer
2k views

Difference between calcination and pyrolysis

What is the difference between calcination and pyrolysis? I understand they both involve heat treatment but each under a different type of atmosphere, which leads to some sort of reduction reaction? ...
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3answers
7k views

Is there a point at which Ethanol (E10) fuel becomes harmful to gas tanks or engines if not used?

This is not the typical chemistry question on this website, but I think it's an important practical question. When I got a gas string trimmer, the woman who worked at the gardening shop told me that ...
4
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1answer
138 views

What is the limiting value of band gap that makes a material semiconductor?

What is the limiting value of band gap (in eV) that makes a material semiconductor? Or what is the value of band gap that separates insulator and semiconductor?
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1answer
41 views

Is it appropriate to call this material a hybrid composite? [closed]

The material I've synthesised is made up of two primary parts at a 1:1 ratio: Part 1: agar, glycerol, water. Part 2: polyurethane resin. The agar mixture on its own was too soft, so I added the ...
2
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4answers
5k views

Why are calorimeters often made of materials with low specific heats?

When building calorimeters, a material with a low specific heat is often used (such as Styrofoam, aluminum, etc.). However, why would a material with a low specific heat be preferred? My thought ...
25
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3answers
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Which is the densest gas known?

Which is the densest gas known to exist under normal "shirt sleeve" conditions: room temperature, one atmosphere, won't explode on contact with air, won't kill everyone in the building in trace ...
0
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1answer
44 views

Are there plastic materials that turn into ceramics? [closed]

Are there other materials that like clay, are plastic (as in they can be shaped by hand) but set to form a hard ceramic, especially ones harder than the fired clay?
5
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1answer
3k views

What is crystallographic equivalence?

I’ve learnt that in crystallography, there are many crystallographic directions that are “equivalent.” For example, in a cubic crystal system, the [011] and [110] and [101] directions are “...
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0answers
25 views

Formic acid and carbon monoxide outgassing from latex mattress

Formic acid is used as a coagulant to turn rubber tree sap into latex, formic acid also decomposes to carbon monoxide. Does this mean things like latex mattresses have the potential to off-gas carbon ...
0
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0answers
52 views

Looking for color changing reaction to track snow layer depth

I'm trying to find a chemical to mark the position of a snow layer with for detection in future seasons. The substance has to be: 1. Colorless 2. Not water soluble/solid 3. Stable for multiple years ...
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4answers
2k views

How does polydimethylsiloxane stick to glass?

Polydimethylsiloxane (PDMS) is the main ingredient in Rain-X, a treatment that adheres to windshields. How does PDMS adhere to class? It can't form covalent Si-O bonds with glass, according to one ...
15
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1answer
632 views

What chemical characteristics give types of steel their properties?

I am a mechanical engineer, and just like everyone else I had classes on the crystal structure of metals, phase diagrams, and the various heat treatments. However, even after diving back into that ...
5
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3answers
2k views

Why plastic sheets contract when heated?

Why do thin plastic sheets contract when heated, contradictory to the behavior of most other materials ? What are the things going on at the molecular level ?
5
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3answers
10k views

Why the atomic (metallic) radius of gallium is less than that of aluminium?

It is a well known fact that on moving down the group of p-block elements, the atomic radius is expected to increase. However, gallium is an exception. The atomic radius i.e., the metallic radius of ...
2
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1answer
87 views

Why n-alkanes can be found in organic solvent extract of rubber?

Sorry for the confusing title, I didn't know how to describe this better. So, if we douse rubber, say, a bicycle tire or a certain type of rubber glove, with organic solvent (n-heptane), we can find n-...
2
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3answers
2k views

Does crystalline glass exist?

As far as I know, glass is a non-crystalline amorphous solid. Does glass exist in crystalline forms? Or is it the definition of glass that it's non-crystalline, in which case my question is based off ...
4
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3answers
6k views

(At what temperature) can salt evaporate?

Related to my previous question, can sodium chloride evaporate, and if so, at what temperature? Since salt is a solid, and apparently all substances can at various temperatures exist as liquids and ...
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0answers
26 views

How to get rid needle clogging on electrospinning of PLA/PCL/PMMA/Collagen?

For my thesis research, I dissolved PLA and PCL in chloroform: methanol (3:1), PMMA (350.000 MW, 13 wt%) in acetone, and collagen in acetate acid--and then, I mixed them together. The problem is when ...
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2answers
127 views

Is “density per unit volume” something?

I was reading articles on the preparation of shellac-based composites when I encountered the following statement (in ref. 1): Wood flour and fibres are interesting because of their low cost, good ...
2
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1answer
32k views

What is the maximum pressure that JB Weld can withstand?

JB Weld, a brand name of steel-reinforced epoxy, makes claims of being the "world's strongest bond". What is the maximum pressure it can withstand, and what is it about the interaction between the ...
4
votes
1answer
90 views

Making Lyophilized Cake Lookalike using household ingredients

I'm working on a machine learning model to identify flaws in vaccines in lyophilized cake form. To train the model, I need a number of samples that look something like this: I have vials, but I'm ...
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0answers
28 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 ...
2
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1answer
131 views

Suitable coating material for protection of sensors

I'm building a moisture/temperature sensor for outdoor use in soil. It uses capacitive sensing for moisture and an NTC thermistor for the temperature. It's going to be used for vegetables so food ...
1
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1answer
64 views

What is the phase transformation temperature anatase to rutile phase in tin dioxide(SnO2)?

Usually people discuss only pressure dependent phase transformations in case of either tin dioxide or titanium dioxide. It would be nice if someone gave the phase diagram for tin dioxide.
2
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1answer
496 views

what is the structure of bamboo kun?

There are claims that the bamboo fiber has inherent antibacterial properties due to "bamboo kun". However I could not find anywhere what is the chemical composition of this "bamboo kun" and also no ...

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