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2 votes
1 answer
114 views

Why is the Molar mass of CO2 different than the weight of the sum of its particles?

The Molar mass of CO2 is stated to be 44.009 grams per mol But in a calculation of the weight of each atom's particles((Electrons,Protons,Neutrons) times Avogadro's constant I get 44.36 grams per mol ...
physicsnewbie's user avatar
0 votes
1 answer
74 views

About whitish layer that formed on chocolate bar

I noticed a whitish layer on the surface of a chocolate bar that I ate yesterday. I looked at the pack where it was mentioned that, "Temperature and humidity changes may cause product to develop ...
Anjankumar's user avatar
-5 votes
1 answer
108 views

betamechaptoethanol smell [closed]

I am doing my masters in science and today one of our neighbors from the other lab came to heat his samples on a heating pad. the samples were in small tubes which contained Betamechaptoethanol, when ...
HHSS's user avatar
  • 1
2 votes
0 answers
29 views

How are gravimetric analyses of particulate matter performed, in order to determine particulate matter concentration in air?

I've been surfing Google Scholar a bit and learned that a common and comparatively less expensive method of measuring particulate matter concentration in air was analysis through gravimetric methods. ...
shintuku's user avatar
  • 121
-1 votes
1 answer
138 views

Is there any chemical that can react with two different chemicals to generate heat or cold? [closed]

For example. There are three chemicals. Chemical A,B,C Chemical B react with Chemical A = heat Chemical B react with Chemical C = cold Is there any chemical available like this? And is it safe to ...
Weirdo's user avatar
  • 7
0 votes
1 answer
349 views

Chemistry behind adding methyl salicylate to iodine dissolved in petroleum jelly [closed]

We did a project at my school where we were asked to create a pain-relieving balm, inspired by Iodex. We first took 50gms of petroleum jelly and heated it in a water bath until it melted and became a ...
Solus's user avatar
  • 35
0 votes
3 answers
5k views

What is mAh/g Specific capacity?

In battery chemistry I've been reading about specific capacities of various electrochemical cells as $\pu{mAh/g}$. For example, in one article it says the specific capacity of the system is $\pu{75 ...
akshaykumark's user avatar
0 votes
1 answer
432 views

What is the best ratio of salt to water when using a salt solution in the electrolysis of water?

I am using the electrolysis of water to provide middle school students with a phenomena to explore chemical and physical change. The set up is producing much more hydrogen gas than oxygen gas and I am ...
Daniel Potts's user avatar
7 votes
1 answer
1k views

Fluorine detection in organic compounds

Many of you will know why I am asking this question. There is a lot of attention recently to the dangers of the so called Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS). In essence organic ...
Boris Hamanov's user avatar
0 votes
0 answers
53 views

Best practices to obtain small quantity of sealed solution without oxidising entire solution?

I'm ordering liquid based chemicals which only come in large bulk quantities. These solutions have a shelf life of approximately 2 years unopened, but 2 - 3 weeks once opened and oxidation kicks in. ...
user115372's user avatar
1 vote
0 answers
41 views

How to prepare an emulsion (compounds in wt%)

I am trying to replicate an experiment to generate microparticles but I found myself confused about how to prepare the ingredients as some need to be weighed and dissolved before and I think the ...
Microbiologie13's user avatar
-4 votes
1 answer
103 views

How Bread is made with yeast, sugar and luke warm milk? [closed]

Materials and Apparatus: wheat flour sugar dry yeast glass bowl covering plate milk Procedure: Lukewarm milk is taken in the glass bowl and sugar is added to it. Then, yeast is added to the same. ...
Dron's user avatar
  • 101
3 votes
0 answers
67 views

Can color-changing leuco dyes be used to indicate when a certain molecule binds to another in a textile fabric?

Thermochromic leuco dyes change color when the temperature changes. I want to use leuco dyes to make a color-changing fabric. However, instead of using temperature to induce color changes, I want the ...
Msamericana1's user avatar
2 votes
1 answer
64 views

Diffusion of multiple gases at once

Graham’s law of diffusion states the rate of diffusion between two gases is inversely proportional to their molar masses. Now, this is helpful when we are focused on two gases. But that is rarely the ...
Alex's user avatar
  • 99
-3 votes
1 answer
490 views

How do I calculate weight percent of BaCl2

A $\pu{0.1036 g}$ sample containing only $\ce{BaCl2}$ and $\ce{NaCl}$ is dissolved in $\pu{50 mL}$ of distilled water. Titrating with $\pu{0.07916 M}$ $\ce{AgNO3}$ requires $\pu{19.46 mL}$ to reach ...
Opeoluwa Yusuf's user avatar

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