Jason Patterson
  • Member for 7 years, 4 months
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How many unique molecules exist? And how many exist only by synthesis?
26 votes

Polymers make this question more or less unanswerable. Consider human chromosome 1, which contains about 249,000,000 base pairs. There is nothing that says we couldn't order those pairs in any way ...

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Why can't carbon form an ionic bond?
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22 votes

$\ce{C^{4+}}$ ions: Single ions are really only observed in the gas phase. There is absolutely nothing that prevents a C4+ ion from being generated in the gas phase, given sufficient energy. Each ...

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Why is active mass of a pure solid or liquid always taken as unity?
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19 votes

Does the activity of a solid or liquid change over the course of a reaction? The density of a solid or liquid reactant doesn't change over the course of a reaction. The mass and volume do as it is ...

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Why do unboiled eggs last longer than boiled eggs?
18 votes

An eggshell is a complex structure. From Wikipedia: Boiling the egg removes the waxy cuticle from the outside of the egg, dissolves a small but not insignificant amount of calcium carbonate from the ...

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Why does superglue ignite cotton?
17 votes

Though the monomers in cyanoacrylate glues contain an ester, their polymerization doesn't rely on that ester group directly. The Wikipedia article for cyanoacrylates shows the polymerization more ...

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Vinegar CH2O ? COH2
14 votes

The reason that acetic acid's chemical formula is often written as $\ce{CH3COOH}$ is that the $\ce{COOH}$ portion of the formula indicates that the compound is a carboxylic acid. You'll also see it ...

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Does everything exist as a gas at p = 0?
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12 votes

Regardless of whether a substance is in a vacuum, it will vaporize if some fraction of its particles have enough energy (due to their temperature) to exceed their binding energy. Binding energy is ...

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Misconception? "That gas is heavier so it sinks."
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11 votes

Without significant mixing, diffusion takes a long time to mix gases. Our understanding of entropy tells us that we will indeed finish with mixed layers, but that doesn't give us a time frame for ...

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Can Ice Packs Freeze Water at 21 °C?
8 votes

It really depends on the initial temperature of the ice packs and their composition. If they start at a temperature far below the freezing point of water, they could conceivably freeze the water as ...

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Experiment to prove that water has air
8 votes

There are two ways that I interpret the question you're asking, and I'll try to address each in turn. If your teacher boiled a container of water and held a piece of glass above it to collect drops ...

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A thermos bottle containing milk is shaken vigorously
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7 votes

A conceptual approach might work better, since the shaking system is not going to convert mechanical energy into thermal energy as neatly as something like Joule's Paddle Wheel. As the bottle is ...

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How to solidify sand
7 votes

I don't know what kind of resolution you're looking for here. If you want a true 3d structure you might be able to create one by taking slices off of the sand bed using adhesive paper. Adding a glue ...

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How many liters of hydrogen gas is produced per gram of aluminium?
6 votes

Your work is correct. I have to assume that this is being graded by a computer, so trivial differences between your answer and the answer that it is expecting matter. Possible source of error 1: ...

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Does humidity increase oxygen levels in the air we breathe?
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6 votes

As to the answer in the title, no, increased humidity does not increase oxygen levels in the air. In fact it does the exact opposite, since the air in each breath will have some fraction displaced by ...

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Why was the prefix 'bi' used in compounds, such as for bicarb of soda?
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6 votes

According to the Online Etymology Dictionary, the word bicarbonate is derived as follows: 1814, bi-carbonate of potash, apparently coined by English chemist William Hyde Wollaston (1766-1828), from ...

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Quantifying CO2 generated/released by the soft drink industry and breweries
6 votes

The xkcd What If? blog, by Randall Munroe, addressed a similar question. He states the result better than I can. For most of the history of civilization, there were about 270 parts per million ...

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Preference of certain positions during chlorination of an alkene
6 votes

In your first example, propene plus chlorine, one of the Cl atoms bonded to a "CH" and the other, that you described as bonding to the end, bonded to a "CH2," so it's not just CH groups getting all of ...

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Which atom goes in the middle of a lewis dot structure?
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6 votes

ETA: I'm unclear about your question. Are you asking why nitrogen isn't the central atom or why sodium isn't? If it's the former, the explanation is below. If it is the latter, sodium, then it's ...

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Mechanics behind auto-ignition temperature
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5 votes

To be clear, I'm no expert on the ASTM standards writers' thinking, and all I have to go on is the standard you've posted. Yes, that's exactly right. Some of the reaction's heat will be lost to the ...

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Copper and hydrochloric acid
5 votes

If pure hydrochloric acid is added to a sample of pure copper, there is essentially no reaction; the solution should not turn blue. At a guess, you're seeing the copper turn pink because it has a ...

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Does the "Bat Gen" claim to produce more energy than it uses?
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5 votes

I'm not sufficiently familiar with the chemistry involved to state authoritatively that this guy is full of bologna, but there are some pretty fantastic claims made in the second link. Also, if that'...

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Volume of different gas in a container
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5 votes

Your second idea, that they have the same volume, is correct. Each gas in a mixture of gases stored in the same container has the volume of that container. Remember that gases are mostly empty space,...

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What does "a metallic oxide has 40 % oxygen" mean?
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5 votes

Your question is a good one, and no, you can't assume that the metal is $\ce{MO}$ necessarily. However, you can find the equivalent weight of the metal without any assumptions about its formula. ...

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Why can't unimolecular reactions be 2nd order?
5 votes

A first order reaction involves the behavior of individual particles, usually their decomposition into smaller, more reactive species. The rate of such a reaction relies solely on the number of ...

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Which atoms in a given amino acid are able to form hydrogen bonds with water?
5 votes

The positive end of water can hydrogen bond with N, O, or F, as you said, but only if A) the geometry of the atom allows the water and N/O/F to get close to one another and B) the N/O/F has a lone ...

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Why doesn't hydrogen displace metals from their oxides?
4 votes

Hydrogen definitely will reduce metal oxides in the right environment. Metal oxides tend to be very stable compounds, and hydrogen, though it is flammable, is not terribly reactive stuff either at ...

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Explanation for behavior of acetic acid in aquaponic/hydroponic systems?
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4 votes

The source of the acid shouldn't matter much in adjusting the pH by a small amount. What is the source of the calcium carbonate? If it is dissolved calcium carbonate only, as you might find in ...

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Why is Electrostatic Potential Energy positive when the charges are like?
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4 votes

There is no way to know the actual potential energy of a system, we can only determine it relative to some predefined zero value. In the case of electrostatic potential, zero potential energy is ...

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Chemicals to clean natural stones
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4 votes

Removing all of the debris from the stones without damaging them can be difficult, the following is what I've done in the past to clean geodes with debris and deposits. Your mileage may vary, ...

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Radioactivity and Kinetics of disintegration
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4 votes

No, as hey answered, neutrons are made of two down quarks and an up quark. Protons are made of two up quarks and a down quark. It is the conversion of a down quark into an up quark that results in ...

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