# Tag Info

Accepted

### Will we ever run out of gold, silver, copper and other important conductors?

How long will these reserves last? Short answer: longer than you think and will outlast me, you, our children and our grandchildren. Possibly last forever. Long answer: This is a fairly complex ...
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### Why is sand, sand; and why is glass, glass; While both mainly contain Silicon Dioxide?

Is it crystallization? You are correct. The main difference is that sand is crystalline and glass is not—it is amorphous. The main component (> 95%) of common yellow sand is quartz (the mineral ...
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### Commercial chalk for kids composition

I am afraid whoever told you "sulfuric acid carbon" does not know the basic terminology (must be from non-chemistry background). There is no such thing as "sulfuric acid carbon" to begin with. Any ...
• 31.7k
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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,...
• 31.7k

### Melting point of obsidian

Obsidian This is a volcanic glass, formed when rhyolitic lavas cool too quickly for crystals to form. From a chemistry point of view, it's a mixture of silicon dioxide, aluminium oxide, with sodium ,...
Accepted

### What is the oxidation state of copper and iron in chalcopyrite?

A number of papers report that the formal valency states of chalcopyrite are best considered as $\ce{Cu+Fe^3+S2}$, based on various computational and spectroscopic evidence. References: Klekovkina, ...
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### How is hair tissue mineral analysis performed?

Inductively Coupled Plasma (ICP) based techniques are very common for elemental analysis. The goal of such analyses is to quantify the elements present in a sample. The neat thing about this, in my ...
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### Why is the only natural source of radium compounds uranium minerals?

You can't find primordial radium because it's half life is too small compared to earths age. Even the radium isotope with the longest half life, $\ce{^{226}Ra}$ has a half life of only 1600 years ...
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### Can olivine be used to make glass?

You could proceed from either end member of the olivine solid series and yield $\ce{SiO2}$ as you suggest. However, I'd consider mechanisms that have been researched in the course of studying so-...
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### Structure of Ca2B6O11

1) Oxygen CAN form 3 or 4 bonds. The most common example is $\ce{H3O+}$ ion This form of bonding is critical to understand basic nature of ammonia solutions, so for exact description of it look that ...
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### How are Uranium and such materials made

Some radioactive materials are made by man, others have been parts of earth's rocks since they were formed Radioactive materials are not all the same. some are man-made and some have been with us ...
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### Commercial chalk for kids composition

Rather pure chalk ($\ce{CaCO_3}$) can be found in the subsoil of huge regions of central France. This chalk can be used for writing on blackboard, but it is too soft. You quickly get whitened fingers ...
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### Why does calcined feldspar crumble?

You're replicating the natural weathering process of granite. Granite is a rock comprising the minerals feldspar, quartz, and mica. There is a continuous solid-solution ternary diagram here that ...
• 10.3k

### How can I determine the chemical composition of local rocks and minerals?

Let's talk about rocks. The art and science of getting useful things from rocks is one of the oldest in human civilization. All of the example products you mention (gunpowder, petroleum, silica, and ...
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