December 10, 2024, 12:45:27 PM
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Organic Chemistry Forum for Graduate Students and Professionals / Handling and storing fuming nitric acid
« Last post by Babcock_Hall on Today at 11:06:28 AM »
In a month or so, we will be using fuming nitric acid for the first time.  We will nitrate a derivative of thiophene on a small scale (50-100 mg?) based on a similar reaction in the literature.  If it goes well, we will scale the reaction up to 250-500 mg.  We will use oven-dried glassware and a nitrogen atmosphere.
(1) Is there anything special in handling this reagent?
(2) After we open the reagent container, how should we store it?  I was thinking of using a small desiccator with some calcium sulfate (Drierite), to minimize its picking up water.
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High School Chemistry Forum / Re: How to calculate number of lone pairs in molecules with odd number of electrons?
« Last post by Hunter2 on Today at 01:49:04 AM »
Read here

https://chemistry.stackexchange.com/questions/173042/how-many-lone-pairs-does-no-have
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High School Chemistry Forum / How to calculate number of lone pairs in molecules with odd number of electrons?
« Last post by NOTEbook on Today at 01:30:49 AM »
How to calculate number of lone pairs in molecules with odd number of electrons? Like in NO there is electron that is not having any pair so how many lone pairs does NO have? Or is lone pair not defined in this case? 
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Citizen Chemist / Re: Strengthening cellophane - types 165 and 180 - while keeping clear and flexible
« Last post by nyurone on Yesterday at 04:41:56 PM »
archival as in Fine Art archival quality. Thank you!
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Citizen Chemist / Re: Strengthening cellophane - types 165 and 180 - while keeping clear and flexible
« Last post by Borek on Yesterday at 04:37:55 PM »
Quote from: nyurone on Yesterday at 03:02:32 PM
P. S. Is there any other archival material(s) (we recently found out that cellophane is not archival) that is pliable/foldable, resistant to tearing, and transparent?

Define "archival material".

For storing old postcards (and other paper memorabilia) mylar envelopes are often used.
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Citizen Chemist / Strengthening cellophane - types 165 and 180 - while keeping clear and flexible
« Last post by nyurone on Yesterday at 03:02:32 PM »
Hello, we are trying to strengthen the clear paper made of cellophane - types 165 (uncoated and thinner) and 180 (coated to increase impermeability and thicker). We want to keep it flexible and foldable, while preventing ripping. We also want it transparent.

These are our initial findings in the PDF but we would like additional comments and feedback to help guide us.

Google Drive Link to the PDF file:

https://drive.google.com/file/d/1-fx3GxV3B1IRi22c1_SWddWoKFlzg9mg/view?usp=sharing

We are not experts, so we need your help.

Thank you!

P. S. Is there any other archival material(s) (we recently found out that cellophane is not archival) that is pliable/foldable, resistant to tearing, and transparent?
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High School Chemistry Forum / Re: What silver solutions will reduce with copper?
« Last post by Hunter2 on Yesterday at 11:41:30 AM »
Does he asking electro less reaction or electrolytical reaction?
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High School Chemistry Forum / Re: What silver solutions will reduce with copper?
« Last post by TriVision on Yesterday at 11:39:04 AM »
It depends on the quality of the chemicals, (not much though) and the magnitude of the DC you are putting through the copper wire. But silver acetate should work- with minimal variation from a standard silver nitrate reduction.
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High School Chemistry Forum / Re: How to check if such reaction occurs?
« Last post by TriVision on Yesterday at 11:35:49 AM »
Clarifying question here; are you asking HOW to check a reaction occurs in a human stomach, or whether to provided formula WOULD react in the human stomach?
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High School Chemistry Forum / Re: Molar Mass
« Last post by TriVision on Yesterday at 11:33:57 AM »
A mole is a measure of amount, like a dozen meaning twelve. When they ask for the number of moles in 20g of Hydrogen gas, you are supposed to convert the 20g of hydrogen to the number of molecules present (your teacher or the problem should provide it, otherwise a simple Google search would do) then convert that number to be represented by moles (which is (6.022 x 10^23 particles). In the second part, you need to double that answer, since it's just H2.
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