Questions tagged [glass]
This tag is for questions relating to glass materials and properties. DO NOT use this tag for questions about glassware.
83 questions
0
votes
0
answers
46
views
Reflux under inert conditions
If a procedure calls for reflux under inert conditions, is it alright if I let nitrogen as protective gas run through the condenser for about 15 minutes, and then attach it to the flask with pre-...
- 471
2
votes
1
answer
118
views
Is it safe to use borosilicate lab glass as an autoclave?
I'm attempting to do a one-pot synthesis that requires autoclaving the chemical mixture. I thought this process would be greatly simplified by using the lab glass itself as the autoclave in situ ...
- 149
5
votes
2
answers
250
views
Why don't oils use plastic droppers?
As shown in the picture, most cosmetic oils and serums make use of glass droppers. However in the chemistry lab, scientists often also use reusable plastic droppers as well. My question was that, ...
- 1,513
2
votes
0
answers
77
views
How can glycerol make glass objects 'disappear'?
There's a famous experiment that uses glycerol (glycerin) to make glass objects 'disappear'. A glass object becomes nearly invisible when filled with glycerol and immersed in a container of the same ...
user145192
1
vote
0
answers
73
views
Alkali-rich lead glass with working range at room temperature
I understand that the glass transition temperature (above which it is considered a super-cooled liquid) is quite far below the liquidus of the corresponding crystalline mixture. In the paper, "...
- 65
-1
votes
3
answers
136
views
Can any compound form into an amorphous solid?
I am curious whether it is possible or not to make any solution of a specific compound into a crystal lattice or into an amorphous solid? I know that crystals form under specific conditions but seem ...
- 265
2
votes
1
answer
60
views
Are there distinct phases of amorphous ice?
Amorphous ice is a solid phase of water that lacks crystal structure. It is stable below about 150K, above which it converts to crystalline ice.
There are four phases of amorphous ice: low medium, ...
- 982
1
vote
0
answers
79
views
Permanent water marks etched onto glass
We are noticing some permanent marks etched onto various glass parts we use in lighting products that cannot be removed. These appear regardless of the type of water (tap, DI etc. Our DI water is ...
- 27
1
vote
0
answers
89
views
Do Boron and Silicon form metallic-type bonds in alloys?
For context I am a physics student currently doing a project that involves metallic glasses. I am trying to figure out if you can get Ionic bonds inside an alloy with metalloids. More specifically, I ...
- 119
2
votes
1
answer
118
views
Diffusion vs mobility and the Einstein relation
This former question is about the mobility constant $M>0$ in the Cahn-Hilliard equation. To determine the value of such a mobility for a simulation study, Kim and Sanders (2020)
use the formula
$$
...
- 193
4
votes
0
answers
116
views
How to estimate the mobility constant and the surface energy parameter in the Cahn-Hilliard equation?
As a mathematician, I want to simulate phase separations with the Cahn-Hilliard equation
$$
\frac{\partial c}{\partial t} = M \Delta \bigg(\frac{\partial \mu}{\partial c} - \kappa \Delta c \bigg),
$$
...
- 193
2
votes
1
answer
72
views
Computing the molar volume for a 2D-simulation of phase separation
I am a mathematician and I want to simulate phase separation that occurs in a sodium silicate glass ($12.5\,\text{Na}_2\text{O}\cdot 87.5\,\text{SiO}_2$) at $T = 923\ \text{K}$ as it was done, for ...
- 193
0
votes
0
answers
71
views
How to define a chemical bond computationally?
I'm working with an amorphous system. With oxygen, my system has both covalent and ionic bond forming cations. I utilise the Wannier centre to define a covalent bond, and my theory is that if the ...
1
vote
1
answer
207
views
Understanding Cahn-Hilliard Equation in terms of Units
The Cahn-Hilliard equation may be formulated as
$$
\frac{\partial c}{\partial t} = M \nabla^2 \left(\frac{\partial \hat f}{\partial c}\right),
$$
where $c : \Omega \to [0,100]$ describes the ...
- 193
5
votes
2
answers
258
views
Understanding the molar free energy to simulate phase separations (Na2O-SiO2)
I am a mathematician and I want to understand the molar free energy model given in Kim and Sanders (2020) Equation (1), that is,
\begin{equation}
f(c,T) = RT \big(c \log(c) + (1-c) \log(1-c)\big) + \...
- 193
4
votes
1
answer
3k
views
How should you report measurements and uncertainty for a measuring cylinder with 0.5 mL graduations?
I understand that a common convention is to report the uncertainty of an analogue instrument as plus or minus half of the smallest scale division.
By this logic, a measuring cylinder with $\pu{0.5 mL}$...
- 135
2
votes
1
answer
2k
views
What are some of the lowest melting point glasses available out there?
I'm wondering about lead-free "glass solder" or any glass frit powder or paste that has a very low melting point (under 400 c). What products are available to the layman, where can I find ...
2
votes
0
answers
104
views
Appropriate ways to remove aluminum from the surface of glass?
I'm looking for a way to treat the surface of borosilicate glassware such that it won't contaminate solutions of puriss reagents in conditions that pure $\ce{SiO2}$ wouldn't, yet keep the bulk ...
- 1,107
-3
votes
1
answer
416
views
Are diamonds as chemically inert as glass? [closed]
Every beaker that I have seen in a lab is made of glass. Glass, as I understand, is made of SiO2, or silicon dioxide, which has a crystalline structure that is similar to diamond. This property causes ...
- 109
7
votes
2
answers
12k
views
How to identify a blow-out pipette?
Is my pipette a blow-out pipette?
I suspect that it is a blow-out pipette, though the double lines aren't rings. My guess is it is a TC blow-out pipette. It's a big 50 mL pipette, longer than my arm.
...
- 197
1
vote
1
answer
470
views
What can be used as substitute to dichloromethane for breaking optical cement bonds?
An optics supply company recommends using a dichloromethane solution to break bonds between optical elements joined with its UV-cured optical cement.1 The page mentions that dichloromethane-based ...
0
votes
0
answers
28
views
Does the process of chemically strengthening glass change its volume?
The process of chemically strengthening glass replaces sodium ions in the glass's surface with potassium ions through a process that uses a potassium nitrate bath solution. These potassium ions are ...
- 101
3
votes
0
answers
238
views
Remove sticky PDMS from glasses slides
I prepared some PDMS mixing a Sylgard 186 (elastomer) and a curing agent with 10:1 ratio. I sucked all the bubbles and I sandwiched the PDMS between two glass slides to get flat surfaces. Finally I ...
1
vote
1
answer
2k
views
when using glass to glass stoppers, is it best to have them dry or use lubricant?
I have some glass flasks that have glass stoppers. It’s basically the typical glass stopper with the frosted tip which fits into a glass opening. Basically think of a typical glass volumetric flask. i ...
- 21
1
vote
0
answers
76
views
Is the width of a Soxhlet Condenser Inherent to its Function?
Soxhlet extractors are often coupled to a specifically designed condenser with a very large lower joint.
Is this inherent to it's function as a condenser in the apparatus or only because the Soxhlet ...
- 1,107
1
vote
1
answer
507
views
Can you measure an IR spectrum of a sample inside a glass vial?
If I have a sample of some compounds dissolved in water inside a glass vial (let's say quartz). Would it be possible to get a usable measurement through this glass vial without too much absorption by ...
- 129
0
votes
1
answer
378
views
What temperature is really required to make fused quartz? [closed]
Glass transition temperature of fused quartz is 1200 °C. Does this mean it can be made by heating sand to 1200 °C, or does the melting point of $\ce{SiO2}$ has to be reached (~1700 °C) for that to ...
- 1,480
2
votes
2
answers
317
views
Does K2CO3 react in minute amounts with glassware at higher temperatures?
At a temperature of $\pu{750 ^\circ C}$, $\ce{K2CO3}$ and $\ce{SiO2}$ react with each other in substantial proportions, forming $\ce{K2SiO3}$ and $\ce{CO2}$ in the process$\ce{^{[1]}}$.
We all know as ...
- 1,107
2
votes
0
answers
36
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 ...
- 553
14
votes
2
answers
2k
views
Can glass be deionized?
Is there a chemical treatment that could remove sodium and calcium ions from the surface of soda-lime glass to turn it into quartz glass, increasing the hardness?
- 1,480
3
votes
1
answer
237
views
What reaction could rubidium undergo in a vacuumed chamber with Macor ceramic and glass?
In the center of the chamber on the photo below you can see the hexagonally-shaped Macor glass-ceramic consisting of
Silicon dioxide $\ce{SiO2}~46\%$
Magnesium oxide $\ce{MgO}~17\%$
Aluminum oxide $\...
- 195
3
votes
1
answer
120
views
Cold process to make glass
Since glass is a mix of silicates of sodium and calcium produced by heating or fusing together $\ce{Na2O}$ (Lewis base) with sand or $\ce{SiO2}$ (Lewis acid). Since $\ce{Na2O/NaOH(aq)}$ is a strong ...
- 69
9
votes
1
answer
2k
views
Gold Plating on Glass?
I am considering labware options to handle NaOH solutions at ~150 °C. One appealing idea would be to coat my current glassware with gold. I've read different sources mentioning the possibility without ...
- 1,107
0
votes
0
answers
868
views
Highly concentrated NaOH solution at high temperature vs borosilicate glassware and cellulose?
I've read here on stack-exchange that NaOH will react with glass through the following reaction:
4 NaOH + SiO2 ⤑ Na4SiO4 + 2 H2O
I would like to briefly heat a highly concentrated NaOH solution to ...
- 1,107
3
votes
1
answer
554
views
How to identify lead crystal glassware?
I would like to identify if a wine glass is made of lead crystal (a destructive method is allowed). Lead crystal is said to be eroded by dishwasher detergent. I don't have a dishwasher, what causes ...
- 131
34
votes
3
answers
5k
views
Why isn't 'chemically-strengthened glass' made with potassium carbonate to begin with?
Instead of making potassium-strengthened glass by creating ordinary soda-lime glass first, then replacing the sodium atoms/ions with potassium by putting the glass in a bath/solution of potassium ...
- 1,833
9
votes
1
answer
139
views
Is it possible to make Prince Rupert’s drops with molten alumina?
When molten glass is dropped into water, you can get tear-shaped objects which are both incredibly strong and which have massive internal stresses. Which means any scratch can cause them to explode.
...
- 1,836
7
votes
1
answer
2k
views
What is wrong with storing deionized water in glass containers?
I have heard that in general storing deionized water in glass bottles is ill advised and that it is better to use plastic. Additionally this is especially important for water used in ICP. I have ...
- 12.7k
1
vote
1
answer
167
views
Cerium (CeO) behavior in Glass Polishing?
I am basically working in semiconductor industry and I specifically taking care of CMP (Chemical Mechanical Polishing). We did polish glass (borosilicate type of glass) and we are using slurry (which ...
- 21
1
vote
2
answers
672
views
How does lime prevent soda lime glass from dissolving in water?
How does lime addition as an ingredient prevent soda lime glass from dissolving in water? Does it form calcium silicate in the process of melting?
- 1,480
1
vote
0
answers
447
views
Copper Mirror Reaction
I would like to create a copper mirror on a plate of sandblasted glass.
I know that a reaction exists:
$$\ce{CuSO4 + N2H2 -> Cu + N2 + H2SO4}$$
I know that such a plate of copper is very weak. ...
- 111
4
votes
1
answer
1k
views
Do xenon di- and tetrafluorides react with glass?
A question came in my test asking which of the compounds are not stored in glass. The answers were $\ce{HF},$ $\ce{XeF6},$ $\ce{XeF4},$ $\ce{XeF2}$.
I know about $\ce{HF}$ and $\ce{XeF6},$ but not ...
- 435
4
votes
2
answers
4k
views
Benefits of a Buchner funnel w/ a fritted disc instead of Quantitative Filter Paper Circles
I was wondering if someone could enlighten me on some example us cases where one would be better of using a Buchner funnel with a fritted disc (example), as opposed to a Buchner "style" filter (...
- 263
10
votes
1
answer
771
views
Why does automotive glass shatter into tiny pieces but glass used in our houses into shards?
Image Source : Bigstockphoto
Image source : pinterest
The first picture depicts the glass that is found from an accident site, while the second picture depicts the glass that we use in our home.
...
- 431
1
vote
1
answer
134
views
How does cullet reduce the production temperature in glass production?
In my book, I read that broken glass pieces are reused in the production of glass, known to be cullet. This on one hand saves the production cost and also reduces the production temperature.
My ...
- 205
3
votes
1
answer
2k
views
Dropping Borosilicate glass mug
I recently got a glass tea mug. It's has double wall construction with a vacuum insulation (advertised as such). I noticed on the label, it specifically mentioned it's made of borosilicate glass, and ...
- 159
3
votes
1
answer
8k
views
Why is xenon hexafluoride not stored in glass?
Why is $\ce{XeF_6}$ not stored in glass containers? Isn't the reason glass is used for most acids is that it is non-reactive?
- 321
3
votes
3
answers
312
views
Carbon in Glass - XPS Analysis
I was reading a paper and found this elemental XPS analysis of an unmodified microscope glass slide surface.
C (1s): 17.7%
Si (2p): 28.47%
O (1s): 53.83%
It seems strange for a piece of normal ...
- 1,369
5
votes
1
answer
884
views
Is the surface of glass a fine layer of silanol?
Today we learned in class through a vivid demonstration that water sticks to glass. We were then taught that water sticks to glass because while glass is mainly composed of silicon dioxide, the ...
- 51
6
votes
0
answers
2k
views
Can a solid be both crystalline and amorphous? [closed]
The first line in the Wikipedia article for "Glass" reads:
Glass is a non-crystalline amorphous solid that is often transparent and has widespread practical, technological, and decorative ...
- 18.8k