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57 votes
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Why is fluorine a gas, but lithium isn't?

A lithium atom has one valence electron, easily lost (shared), so it is connected to other atoms by a metallic bond. This is a bit like the shell game where a pea (electron) is hidden under a walnut ...
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33 votes
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Why do the alkali metals form different products upon combustion in air?

Since I will deal with all of the alkali metals in this answer, I think the question should also be broadened. There is no point in covering one single metal (sodium) without touching the others since ...
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31 votes
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What metals aren't dissolved in/attacked by aqua regia?

Keep in mind The answer will depend upon the reaction conditions. Most importantly, physical state of the metal: porosity, degree of comminution; temperature; mechanical aggravation of metal surface ...
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30 votes

Why does zinc react with sodium hydroxide?

Indeed, $\ce{Zn}$ is lower than $\ce{Na}$ in activity series of metals, so the following reaction won't take place $$\require{cancel}\ce{Zn + 2NaOH \cancel{→} Zn(OH)2 + 2Na}$$ Remember, however, ...
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28 votes
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Could milk rust a steel teaspoon?

Technically, even simple water can cause rust, so nothing surprising here. However, spoilage of milk most probably produced a lot of organic acids (lactic acid and similar) which can speed up any ...
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26 votes
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Can metals have a net negative charge

These species usually do not exist in nature, but they can be synthesized. Silver has been reduced in liquid ammonia to give $\ce{Ag-}$. A lot of anionic metal carbonyl complexes $\ce{M(CO)_{n}^{m-}}$...
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25 votes
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Gaseous metals?

No, gaseous metals do not retain metallic bonds, nor metallic conductivity, nor luster, nor any other metallic properties. They are no different from other gases. True, they typically require pretty ...
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25 votes
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Why do only some metals make protective oxide layers?

The simple answer is that metals which form sufficiently insoluble oxide layers stifle the very process which caused the oxide layer in the first place. It's not just a matter of energy of formation ...
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23 votes
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Why is gold unreactive when only one electron is in the outer shell?

First off, gold does react. You can form stable gold alloys and gold compounds. It's just hard, mostly for reasons explained by the other answer The reason bulk gold solid is largely unreactive is ...
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23 votes

How toxic chemically is plutonium (Pu), neglecting the radioactive damage?

The toxicity is primarily due to radioactivity and to absorption by the body, where that radioactivity can act internally. There is, "significant deposition of plutonium in the liver and in the &...
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22 votes
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What causes the iridescent colour in laboratory grown bismuth?

The colour is from a thin film of bismuth(III) oxide that forms on the surface if the crystals are formed in air. At the elevated temperatures used to melt bismuth, the oxide forms quite quickly. The ...
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21 votes

Why did the salt on the skin of my turkey react with the aluminum foil it was touching?

If you don't mind, I'll start with a more colloquial and hopfully not to lengthy explanation: Precious metals, such gold, do not corrode under "household conditions", others, such as iron or ...
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21 votes
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How to think of solvated electrons?

The analogy with a proton is actually a good one if you are careful to remember that an electron is nearly 2000 times lighter than a proton. What does that mean? It means that despite the fact that an ...
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21 votes

How is aqua regia stored?

How is aqua regia stored as it dissolves all metals? No one stores aqua regia for extended periods of time, because it decomposes rapidly, yielding volatile products that escape from the solution ...
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20 votes
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Turn lead into gold via radioactive decay

Interesting idea, but it has already been done, and not cheaply - read on. How could we get a great quantity of $\ce{_{82}^{197}Pb}$ ? There would be two problems with getting a large amount of $\...
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20 votes
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Are there colorful metals besides gold and copper?

Osmium has a bluish-gray tint. Well; slightly. Cesium is silvery-golden!, But don't wear it.
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19 votes
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What is happening in this video of solvated electrons donated from sodium in ammonia?

I'll try an answer to this question because I watched this video a while back and did a bit of reading on it at the time and I think I understand the big picture. The problem is that these solvated ...
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19 votes

How toxic chemically is plutonium (Pu), neglecting the radioactive damage?

Actual toxicity other than radioactivity is not, as far as I know, very well studied. Quite simply, most of the danger is the radioactivity in general, as well as the toxicity of decay products (...
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18 votes
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Mercury metal: Not toxic?

Mercury is toxic, but you need to carefully define what you mean by toxic or you draw incorrect conclusions Toxic is a broad term. It means a lot of different things. The timescale matters. Some ...
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18 votes
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How is hair tissue mineral analysis performed?

The analytical technique is called inductively coupled plasma optical emission spectroscopy. It was invented by a chemist V. A. Fassel, although it is pure physics. The specimen is digested in an acid,...
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17 votes

Why is gold unreactive when only one electron is in the outer shell?

Relativistic effects account for gold's lack of reactivity. Gold has a heavy enough nucleus that its electrons must travel at speeds nearing the speed of light to prevent them from falling into the ...
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16 votes

Platinum group metals: Why are platinum and palladium great catalysts and not the others?

I think some of the other transition elements have also catalytic properties. For example, rhodium is generally used in addition to platinum or palladium in catalytic converters to oxidize carbon ...
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15 votes

How can steel be so different from iron, even if amount of carbon is small?

One of the key considerations is that much of the interesting mechanical behaviour doesn't occur within the bulk of the material - it occurs at the interfaces between crystals (known as grains). Grain ...
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14 votes
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Why is zinc more reactive than copper?

You have to think about the whole process. When a metal loses electrons to make a metal ion the following happens: The metallic bonds holding the metal atoms together are broken. The metal atom ...
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14 votes

What metals aren't dissolved in/attacked by aqua regia?

What metals (elemental, forget alloys) are neither attacked by nor dissolved in (freshly prepared) aqua regia? At normal condition, most of the metals are impervious to aqua regia but if the ...
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14 votes

Do metals form covalent bonds besides ionic and cordinate bond?

The first thing that should be said is that there's no difference between a coordinate bond (dative bond) and an ordinary covalent bond. Yes, the electrons "come from different places"; but the ...
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13 votes

Why does aluminum have a lower first ionization energy than magnesium?

The easiest way to explain it is that $\ce{Al}$ has one unpaired electron in it's highest energy orbital ($\mathrm{3p}$), and $\ce{Mg}$'s highest energy orbital ($\mathrm{3s}$) the electrons are ...
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13 votes

Are there colorful metals besides gold and copper?

There is no element other than gold and copper with similar colors; see http://periodictable.com/Properties/A/Color.html. There are many metal alloys that are red and golden, such as phosphor bronze,...
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13 votes
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How could I cause metal to rust rapidly?

Here are factors that would speed up rusting: Presence of water: make sure that the iron is wet. Presence of oxygen: make sure the iron have access to air (the dissolved oxygen in water also works). ...
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