Teen Stuff at the Library

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Jul 5

skunkbear:

What makes fireworks colorful?

It all thanks to the luminescence of metals. When certain metals are heated (over a flame or in a hot explosion) their electrons jump up to a higher energy state. When those electrons fall back down, they emit specific frequencies of light - and each chemical has a unique emission spectrum.

You can see that the most prominent bands in the spectra above match the firework colors. The colors often burn brighter with the addition of an electron donor like Chlorine (Cl). 

But the metals alone wouldn’t look like much. They need to be excited. Black powder (mostly nitrates like KNO3) provides oxygen for the rapid reduction of charcoal (C) to create a lot hot expanding gas - the BOOM. That, in turn, provides the energy for luminescence - the AWWWW.

Aluminium has a special role — it emits a bright white light … and makes sparks!

Images: Charles D. Winters, Andrew Lambert Photography / Science Source, iStockphoto, Epic Fireworks, Softyx, Mark Schellhase, Walkerma, Firetwister, Rob Lavinsky, iRocks.com, Søren Wedel Nielsen

(Source: patiences4not)

(Source: frostingpeetaswounds)

(Source: captain-rogerz)

dbvictoria:

Shakespearean insults, with cats.

7 more here.

thelonelyscarecrow:

castiels-time-traveler:

nintendocanada:

mapsontheweb:

Map of the World by Natural Skin Color

i’m really dumbfounded that i never realized skin colour is literally just caused by being closer to or farther from the equator and the resulting sun exposure and skin darkening

actually, its an adaptation. natural selection. people with darker skin are selected for in areas near the equator, where the melanin that causes the darker color protects them from radiation and protects them from skin cancer and other health defects, and because they are healthier they can pass on that trait more. people near the poles have lighter skin because it allows them absorb more of the limited sunlight to convert to vitamin d. 

THIS IS THE THING SOME PEOPLE HATE OTHER PEOPLE OVER.Evolution of melanin levels based on geographical location.

thelonelyscarecrow:

castiels-time-traveler:

nintendocanada:

mapsontheweb:

Map of the World by Natural Skin Color

i’m really dumbfounded that i never realized skin colour is literally just caused by being closer to or farther from the equator and the resulting sun exposure and skin darkening

actually, its an adaptation. natural selection. people with darker skin are selected for in areas near the equator, where the melanin that causes the darker color protects them from radiation and protects them from skin cancer and other health defects, and because they are healthier they can pass on that trait more. people near the poles have lighter skin because it allows them absorb more of the limited sunlight to convert to vitamin d. 

THIS IS THE THING SOME PEOPLE HATE OTHER PEOPLE OVER.

Evolution of melanin levels based on geographical location.

(Source: transenoughblog)

handaxe:

The Columbine shooters, Eric Harris and Dylan Klebold had not been bullied to the point of retribution. They were bullies. Dylan had been suspended for etching “F*G” into another student’s locker. Eric had a list of girls on his computer titled “Shit List” and they’d all slighted him in some minor way. He was also really into Nazi Germany and would give the nazi salute and said “Heil Hitler” a lot. They made fun of fat kids. They made fun of kids with speech impediments and disabilities.

They would go out at night on “missions” and vandalize other student’s houses for having “wronged” them in some way, but really they attacked students who they thought were inferior. It started out fairly innocuous, they’d drink and go toilet paper someone’s house- but eventually they implemented fire crackers. Soon enough they were shooting at student’s houses and breaking windows. Soon enough they were setting off pipe bombs.

The local police had been contacted about Eric Harris and Dylan Klebold two years prior to the shooting. They drafted up a search warrant but never acted on it. 

tastefullyoffensive:

King Carl XVI Gustaf of Sweden Wearing Silly Hats [via]

Previously: Celebrity Faceswaps

victorvigny:

Ah yes thank you that’s exactly what I meant.

victorvigny:

Ah yes thank you that’s exactly what I meant.

(Source: firefoxacademy)