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1500 questions
16
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Why are the plastic balls used to reduce evaporation in this reservoir black instead of white?
Plastic balls have been added to a reservoir in drought stricken California in order to reduce evaporation. (Link to news story here.)
Why are the balls colored black instead of white? I would think that white would decrease heating and therefore…
Brinn Belyea
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16
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Why atomic masses aren't integers?
Most of the elements have isotopes, so the atomic masses are calculated depending on the percentage of the existing isotopes. That is clear. However, what about elements that have only one isotope (monoisotopic) - like fluorine? Shouldn't the atomic…
waterlemon
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16
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Does bleach (without rinsing) leave residues and can vinegar, baking soda neutralize them?
It's very difficult to get accurate information concerning household bleach residues. Imagine, for instance, that you pour pure (or diluted) bleach onto fabric or synthetic foam and let it dry without rinsing (as a scientific experiment). Some…
JinSnow
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Byproducts in Indigo Synthesis?
I have been messing around with making Indigo dye while waiting for bacteria to grow. I have been following the Baeyer-Drewson method. Basically, you mix nitrobenzaldehyde with an acetone water mix and slowly add NaOH. The solution turns black and…
user137
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How is spiro[4.4]nonatetraene antiaromatic
How is spiro[4.4]nonatetraene antiaromatic? I know that spiro compounds exhibit homoaromaticity, but how do they exhibit antiaromaticity?
EJC
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16
votes
3 answers
Which one is the best notation for sodium acetate
I have seen two different notations for sodium acetate. The first one is:
$$\text{NaCH}_3\text{COO}$$
The second one is:
$$\text{CH}_3\text{COONa}$$
Now I'm confused, which one is the best to use?
Adnan
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16
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2 answers
Diagonal relationships in the Periodic Table
I have often wondered about diagonal relationships between elements on the periodic table, and the most often cited explanations revolve around charge-density considerations.
But other than that, what other factors could possibly contribute to this…
getafix
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16
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1 answer
Why do some solvents bubble more than others when boiling?
This question about boiling milk reminded me of my everyday lab work at the rotavap: Some solvents and solutes are feared for the intense bubbling they create while the solution is boiling — be it at ambient pressure like the milk or at reduced…
Jan
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16
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1 answer
Why do halogen-metal exchanges happen?
I'm trying to understand organometallic raegents but am stuck at halogen-metal exchanges.
For example if you have $\ce{PhBr + BuLi}$ you get $\ce{PhLi + BuBr}$, I don't understand why $\ce{PhBu + BrLi}$ wouldn't form.
Ian Xul
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16
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2 answers
Molten vs Liquid
When I start studying electrochemistry, I learn the words “molten” and “aqueous”. I don't have a problem for “aqueous”, but I'm a little bit confused about “molten”.
For me, “molten” means melt, which means to become liquid from solid. But why do we…
Simon-Nail-It
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16
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2 answers
When I heat up a balloon, does the air inside increase in pressure as well as volume?
When I heat up a balloon, does the air inside the balloon increase in pressure as well as volume? I thought pressure and volume were inversely proportional? Or does pressure and volume increase as temperature increases?
John
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16
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Is azide paramagnetic?
Is the azide ion ($\ce{N3-}$) paramagnetic?
How do I use molecular orbital theory to show that it is or isn't?
I drew a sine wave diagram and filled up the $1\pi$ and $2\pi$ MOs, and since there are no unpaired electrons, can I conclude that the…
kane9530
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16
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1 answer
Lewis Structure on (CH3)2NO?
I've been taking an chemistry class online (for fun only) and one of the questions in the homework threw me a bit. Here's the wording:
"Draw the Lewis structure for a nitrogen atom attached to. two methyl groups ($\ce{CH3}$) and one oxygen…
Andrew
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16
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3 answers
Friedel–Crafts reaction of phenol
Does phenol undergo Friedel–Crafts reactions or does it react with Lewis acids like aniline does?
user63762453
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16
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Resolution in Mass Spectrometry
I have been reading about resolution in mass spectrometry and there are a few things I do not understand.
The resolving power is determined by $m/(m_2-m_1)$ at full width half height of a peak. The higher the value obtained the better. This is where…
Harpal
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