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Bulk gold has a very characteristic warm yellow shine to it, whereas almost all other metals have a grey or silvery color. Where does this come from? I have heard that this property arises from ...
tschoppi's user avatar
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244 votes
1 answer
76k views

If I can smell an object, it means that molecules are getting separated from it, so they can reach my nose. As far as I know, metals don't sublimate, especially not at room temperature. However, ...
vsz's user avatar
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185 votes
8 answers
177k views

According to some chemistry textbooks, the maximum number of valence electrons for an atom is 8, but the reason for this is not explained. So, can an atom have more than 8 valence electrons? If ...
MWt's user avatar
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147 votes
7 answers
56k views

Hydrogen is flammable, and for any fire to burn it needs oxygen. Why does a compound made of hydrogen and oxygen put out fires instead of catalyzing them? I understand that hydrogen and water are ...
Prageeth Saravanan's user avatar
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127 votes
8 answers
34k views

We were dealing with the Third Law of Thermodynamics in class, and my teacher mentioned something that we found quite fascinating: It is physically impossible to attain a temperature of zero kelvin ...
paracetamol's user avatar
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125 votes
7 answers
95k views

A friend of mine was looking over the definition of pH and was wondering if it is possible to have a negative pH. From the equation below, it certainly seems mathematically possible—if you have a $1.1$...
apnorton's user avatar
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115 votes
1 answer
6k views

There have been various explanations posited for the α-effect. The α-effect refers to a phenomenon wherein nucleophiles with lone pairs on atoms adjacent (i.e., in the α- position) to the atom bearing ...
Greg E.'s user avatar
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113 votes
5 answers
89k views

At the Renaissance fair a few years back I was watching a smith forge metal into shapes. During this time a very odd question came to me. I was wondering what the furnace was made of. My logic stated ...
Griffin's user avatar
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107 votes
7 answers
350k views

In the TV show "Breaking Bad", Walter White frequently gets rid of people who get in his way by submerging them in a plastic container full of hydrofluoric acid. This, at least in the TV show, ...
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103 votes
7 answers
144k views

My chemistry book explains that even though electrons in the $\mathrm{2p}$ orbital are closer to the nucleus on average, electrons from the $\mathrm{2s}$ orbital spend a very short time very close to ...
Gordon Gustafson's user avatar
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103 votes
2 answers
41k views

I'm all bent out of shape trying to figure out what Bent's rule means. I have several formulations of it, and the most common formulation is also the hardest to understand. Atomic s character ...
Dissenter's user avatar
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98 votes
7 answers
71k views

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 ...
Simon-Nail-It's user avatar
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91 votes
5 answers
21k views

I believe I saw this claim somewhere on the internet a long time ago. Specifically, it was claimed that the difference could be observed by filling one long, straight tube with light water and one ...
Brian's user avatar
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88 votes
5 answers
114k views

Among my friends it is a sort of 'common wisdom' that you should throw away water after a couple of days if it was taken from the tap and stored in a bottle outside the fridge, because it has 'gone ...
Michiel's user avatar
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87 votes
3 answers
6k views

The most notable characteristic of polytetrafluoroethylene (PTFE, DuPont's Teflon) is that nothing sticks to it. This complete inertness is attributed to the fluorine atoms completely shielding the ...
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