Amaton

I'm no chemist, but I think gum's lack of solubility with water is the culprit here. The same property keeps gum from absorbing saliva and dissolving like normal food would. Thus it also resists cleaning, since you can't use water to break it down or cause it to lose its grip on porous materials like asphalt (which also has water repellent properties).

That makes sense. It also explains why we need special (and relatively expensive) chemicals to break it down instead of water-based cleaners.

http://www.acs.org/content/acs/en/sustainability/archive/news-a-greener-chewing-gum.html

"The latest news about nonadhesive chewing gum comes from University College Cork (Ireland). In early November, the university announced that Elke Arendt and her research team at the School of Food and Nutritional Sciences developed and patented a nonstick, biodegradable chewing gum from cereal proteins. Professor Arendt says that their product tastes and feels like the synthetic products, but it safely dissolves in your mouth after 45 minutes. Tossed-out gum is easily picked up or swept away. Although the manufacturing technology for this gum is completely different from current processes, several companies are interested in its possibilities."

I'm sure Disney World, Six Flags, and all big cities are also interested in the idea.

 

Frankly I was more scared of the legions of fanatically friendly and horrendously helpful purple clad volunteers. The security was long-term and (group 4 aside) well planned - I cycled past the main park and arena twice a day and was amazed at the efficiency of almost every level of organisation. It was indeed a major target - and I thank Darwin that no one was able to breach the security; I wonder if we will ever find out if anyone tried?

I don't remember any specific news about Muslim extremists against London as there is now with Russia. I'm sure there was at least one plan plotted against the events, especially with something as big as London. If one was attempted, then it never came to fruition. All it takes is just a single lunatic, like in Atlanta, but Russia is already threatened by organized terrorism.

Really, no one? It's just a matter of what's going on chemically between the gum and rubber material.

With all the recent news of terrorist threats, I'm thinking back to London 2012, Canada 2010, and China 2008.

Why did it seem like these events never had so much of an issue with security? Was I just unaware of pre-game news for these places, or are there particular reasons that Sochi, Russia is a target? I'm thinking it has to do more with Russia itself?

From the Wikipedia article on Chewing gum...

"It is extremely difficult and expensive to remove once "walked in" and dried. Gum bonds strongly to asphalt and rubber shoe soles because they are all made from polymeric hydrocarbons. It also bonds strongly with concrete paving."

So what exactly is this bonding between polymeric hydrocarbons? From my little general chemistry knowledge, I would guess a type of intermolecular force. A typical person would never guess the annoyingness of stuck gum would have anything to do with chemistry (then again, everything has something to do with chemistry). Just curious.

I would like to point out, in regards to pi in base pi being ten, that in fact how would you define pi as a base?

 

For one, calculated in different bases, the number differs.

What do you mean by "the number differs"? The way we represent a number in writing changes between different bases, but the actual value of the number does not.

You may be asking something else, though, in which case, please correct me.

 

I'm really baffled what the point of this video is. It isn't funny. It isn't a vaguely convincing lie. It is just stupid.

I haven't bothered to watch the whole video, but maybe this is one of those "hoaxes", a well-presented gag to see how the audience reacts -- like dihydrogen monoxide.

Ok ok, ok, so I just watched a video thats said theres chlorine in most tap water, so, is this true? if it is, the amount in tap water is harmful or not, http://www.youtube.com/watch?v=qPKE9phMGSg, there

In my opinion, it's best to ignore any such claim made by a company wanting to sell its product. When science is involved in advertising, the propaganda method tends to be fear, and that's when truth becomes of secondary to negligible priority.

You should cross-check the claim with information from a reliable (scientific) source, though this particular topic may not be so well documented. At best for something... Water chlorination - Wikipedia, the free encyclopedia

 

Arsenic(III) sulfide sublimes readily, even below its melting point of 320 °C. The molecules of the vapor phase are found to effuse through a tiny hole at 0.28 times the rate of effusion of Ar atoms under the same conditions of temperature and pressure. What is the molecular formula of arsenic(III) sulfide in the gas phase?

This should essentially be an effusion-rate problem. I know the equation is [math]\dfrac{r_x}{r_y}=\sqrt{\dfrac{M_y}{M_x}}[/math], where [math]r[/math] is the rate of effusion and [math]M[/math] is molar mass.

I know [math]M_{Ar}=39.95[/math] g and the effusion rate for arsenic(III) sulfide is [math]r=.28r_{Ar}[/math].

Therefore, [math]\dfrac{r_{Ar}}{0.28r_{Ar}}=\sqrt{\dfrac{M}{39.95g}}[/math]. I'm trying to find [math]M[/math].

After the math, I get [math]M=509.6[/math] g (to 4 significant figures).

The closest working ratio for the arsenic compound seems to be two formula units, As₄S₆. This is the textbook answer. However, this molar mass is [math]492.04[/math] g, a bit far off from my answer. Why? Did I go about this wrong?

The idea of "principal" square root is a matter of convention. Mathematically both square roots are equally valid.

Thanks guys. I was only thinking about a real argument in the square root, but now I also know something about the complex function.

It would have to, because z^2/2 is also (z²)^1/2, and (z^a)^b=z^ab. Because 2/2=1, then z^2/2=z¹=z. That is also (z²)^1/2, so therefore it is.

It would have to be what? I can't tell what you're arguing for.

Is [math]z^{\frac{1}{2}}[/math] equivalent to the principal square root or the plus-minus square root?

[math]\log_5 (x-1)+\log_5 (x-2)-\log_5 (x+6)=0[/math]

There are probably more efficient ways, but the first thing I thought of doing was...

[math]5^{\log_5 (x-1)+\log_5 (x-2)-\log_5 (x+6)}=5^0[/math]

Take 5 to the power of both sides. After some simplification...

[math]\frac{(x-1)(x-2)}{x+6}=1[/math]

From there, you can bring out the denominator to the other side and rearrange the equation into standard quadratic form.

Eg. p=p实-p内

Eg. p总V总=nRT

Eg. (delta)U=U生-U反

If no one here can answer, then ask an appropriate instructor/professor.

Nonetheless, you can attempt to draw parallels from the English equivalents of those formulae. However, some ambiguity remains with the uncertainty.

I'm kind of new to chemistry, and from what I know, aqueous means something is readily dissolved in water.

Not exactly. If you see that a particular substance is "aqueous", then you should assume that the substance is actually in solution, more specifically an aqueous solution (i.e. the solvent is water). Whether or not something "can / cannot / maybe so" dissolve in water has to do with different terminology.

It's like the three common states of matter. Typically in a lab, you're not going to talk about whether a sample of water could be frozen, liquid, or gaseous. You want to know its actual state, what form it's in.

Likewise, if a substance is completely dissolved in water, then you have water molecules separating and surrounding the particles of that substance. You can't really say whether the substance itself is in solid, liquid, or gas phase. None of those three terms really describe a kind of state where you have individual particles freely floating around in solution, so we say it's aqueous if the solvent is water.

And, well, I feel he's really patient and even-tempered.

I strongly agree; he's been very cooperative for such a discussion -- and on several threads also. These would have been closed already by the forum's typical conventions.

What is the argument of -i?

On an Argand diagram, there is only 1 line...

How would you write this in the form [math]a+bi[/math]? From there, you will know the real and the imaginary parts needed to find its argument.

There is an excellent recent book discussing this issue. The book is titled "Animal Wise (The Thoughts and Emotions of Our Fellow Creatures)" by Virginia Morell. The book discusses the Mirror Self Recognition Test (MSR). According to the author, the Mirror Self Recognition test has come to regarded as the gold standard in determining if species other than chimps and humans possess self-awareness. For example, if an animal such as a dolphin or a parrot can recognise itself in a mirror, then it is considered to be self-aware, and hence to possess a level of consciousness.

Funny, because some dogs are apparently unable to recognize themselves in a mirror -- which brings up the question, how is consciousness defined in that context? Strangely, I can't come to define the term other than attributing it to a complex mess of poorly understood phenomena.

Self-awareness and metacognition don't seem like the minimal requirements of "consciousness" to me, but then again, I'm no authority on the subject. I guess "sentience" seems to be more fitting for the term, while self-awareness is an elevated form nearer to sapience.

My entire life, I've had this peculiar relationship with a common food favorite -- chocolate.

Nearly every time I eat something with a lot of chocolate, there's a sneeze or two. Name any chocolate-rich treat, and if it goes into my mouth, I can't help but sneeze. This typically only happens with the first bite. After that, I can chunk down on it without any other noticeable effects.

The same happens with strong mint, and I'm sure I'm not the only one on this forum who has such a reaction to either or both. I used to think it was some very mild form of allergy, but upon research this is most likely not the case.

The conditions are allegedly related to a much more common phenomenon known as photic sneeze reflex, where affected individuals have an involuntary sneeze when suddenly exposed to a large amount of light, especially in regards to the face.

> http://www.scientificamerican.com/article.cfm?id=looking-at-the-sun-can-trigger-a-sneeze

While the above condition is actually relatively well studied, chocolate and other food-related reactions do not seem to be so well documented (but there are some sources, albeit nonscientific).

> http://www.theatlantic.com/health/archive/2010/07/for-some-chocoholics-an-orgasm-of-the-face/59885/

Interestingly, all these anomalies seem to be related in that the individuals supposedly inherit these via a dominant trait, meaning that one or more biological family members are also likely to have it.

Well, I don't really have a question, but I thought this would be an interesting topic to bring up. Thoughts? Any similar circumstances to share?

 

This experiment doesn't say matter can be made out of photons, it is saying that photons behave as though they have a rest mass. They are completely different statements. I noticed some bad journalism writes the article headlines as ''scientists make matter from light'' this statement isn't true. Light is imitating particles with mass.

So this isn't really a "feat that runs counter to decades of scientific belief", but rather an observation of past's theory?

Can someone explain to me mathematically, in terms of Axis, and or in word form what the 5Th dimension is?

What context are we talking here? Because "the 5th dimension" could refer to several things.

If you're thinking purely geometric, then you're probably looking for the 5th spatial dimension (as opposed to an extra dimension of time or some application in physics).

The general notion with spatial dimensions is surprisingly simple. The first spatial dimension has one axis, typically referred to as the [math]x[/math]-axis. The second dimension has two axes, the [math]x[/math]-axis and the [math]y-axis[/math] forming the [math]xy[/math] plane. Likewise, the third dimension has three axes forming an "xyz space" (very informal wording).

When we go beyond the 3rd spatial dimension, things get hard to visualize, but conceptually it all follows the same basic principle. Four spatial dimensions include 4 axes, conventionally wxyz. Five dimensions: five axes; etc. etc. As you can see, for any (simple Euclidean) spatial dimension [math]n[/math], we will have [math]n[/math] axes (given [math]n\ge 0[/math]), each perpendicular to all the others if defined.

An interesting bonus fact... The surface of a 5-dimensional hypersphere consists of infinitely many 4-dimensional hyperspheres which themselves each consist of infinitely more spheres. It's somewhat of a word salad, and in a purely mathematical sense, it's really nothing special. Regardless, it's a mindrape in trying to wrap one's head around such an object, as if the 4th spatial dimensional alone wasn't crazy enough.

Congrats mutatis! Like many say, you just won the internet

And I feel like I owe an intellectual apology to Daedelus. I unreasonably assumed this would be like most math puzzles one is familiar with, short and competitive (quite wrong on that). It was pretty frustrating, but it felt really good to dive into a problem that actually takes up your time and forces you to think.

This is much trickier than I thought it would be.

I attempted a start by having the two quadratics in vertex form...

[math]f(x)=p(x-m)^2+h[/math]

[math]g(x)=q(x-n)^2+h[/math]

...with the [math]h[/math] parameter to secure the "equal heights" part, and also [math]p,q<0[/math] to ensure that it reflects the functions' maxima.

I tried to reconcile my start with your equation using corresponding terms, but the resulting system is very messy. Then, I tried your method purely, but I failed to solve for [math]a, b, c[/math] without running into an inconsistency or tautology. Blargh!

There is some semantic innuendo to do with your question. The problem with finding a cure for cancer is that there probably isn't one. "Cancer" encompasses many diseases each with their own complications to the respective region they affect, i.e. no universal cure -- so even if one were to cure a particular kind of cancer, that does not guarantee any immediate success for the other kinds.

Simplistically, cancer results from a group of cells stuck in perpetual mitosis. At first, I thought a universal cure would be realistic as long as we focus on fixing that perpetual mitosis. However, one quickly realizes that a botched cell cycle has many potential causes, each with its own complicated mechanism. Nonetheless, your question still stands. Even with teams of scientists focusing on those specific mechanisms, why have none of them found a cure for just one of all the many different types of cancer?

I think I have a solution, but I'm not sure if I understand the scenario correctly...

So we have two distinct quadratics with equal height but nothing more specific, and two distinct points but nothing more specific, i.e. all expressions and functions are generalized?

 

Yeah that would be extremely intuitive haha, some weird fraction being the radian measurement for 90 degrees lol

Maybe not so bad. [math]H(\pi,\tau)=\dfrac{2}{\frac{1}{\pi}+\frac{1}{\tau}}=\frac{4}{3}\pi=\frac{2}{3}\tau[/math].

Ah! Let's denote this constant [math]\eta[/math]. The volume of the space enclosed by a sphere is [math]V=\eta r^3[/math]. Now where's my Nobel Prize?