An atom is the smallest particle of its Element that still has its elements properties. Like if you took apart a Atom of Iron then it would no be Iron it would be Protons,Neutrons and electrons. An Atom is made up of Protons,Neutrons and Electrons. These are subatomic-particles. The positively charged + Protons and the no charge neutrons make up the center of the Atom, the Nucleus. Particles called Gluons ( you can learn more about Gluons in the Quantum Physics part of the next part ) and the Strong force keeps the Nucleus together. The Negatively charged - Electrons whiz and whirl around the Nucleus in a cloud. They are at different shells. The rest of the Atom is Empty space. The Nucleus is Extremely dense. The Protons and Neutrons are made out of Quarks. An Atoms Properties are determined by the number of Protons,Neutrons and Electrons, like Silver has 47 protons ( and electrons if it is a neutral Atom) while Gold has 79 protons. Atoms are Incredibly small. A Human hair is one million carbon atoms wide.
I think It is crazy that everything is mostly made of .... nothing.
Isotopes and Ions
Isotopes are Atoms with different numbers of Neutrons. Take carbon, It has 6 protons no matter what but the number of neutrons can change. The most common isotope of carbon is C12 it had 6 protons and 6 neutrons but C14 is another isotope of Carbon. It has 6 protons but is has 8 neutrons. That is Isotopes. Ions are Atoms with charges. If a Atom lost or gained an Electron it would become an Ion. It would only lose or gain electrons that are on its outer shell/Valence shell. Losing an electron makes it have more protons than electrons. This gives it a Positive charge. It is a Cation. Atoms that have almost no Valence electrons ( Electrons on the outer shell) would more likely give it up to have a full Valence shell. Atoms want full Valence shells to be Stable. If it Gained an Electron the Atom would have a negative charge. It would be a Anion. Atoms that have almost full Valence shells would be more likely to gain and electron. Negatively charged and Positively charged Atom are attracted to each other. This is one way atoms bond, it is called the Ionic bond.They bond to form Molecules, groups of 2 or more Atoms. A example of an Ionic bond is Sodium chloride/NaCl or Salt. Sodium has only one Valence Electron. It dose not take much energy to take that electron. Chlorine almost has a full Valence shell. All it needs is one more Electron. So Chlorine takes the Electron and becomes an Anion and Sodium becomes a Cation. The Opposite charges attract each other like Magnets and they form salt. The Sodium side of the Molecule is slightly positive and the Chlorine side is slightly negative. This is a Polar Ionic bond. Polar molecules have poles. This is how the Molecules combine to make Large amounts of salt.
Chemical Bonds and Chemical equations
Chemical Bonds hold atoms together to form Molecules. Another way Atoms bonds is called the covalent bond. Hydrogen is made with two Hydrogen atoms, they bond with a covalent bond. Both atoms only have one valence electron. But when they bond they share Valence electrons and each can "pretend" that they have a full valence shell. H2O Water is made with a polar covalent bond. Oxygen has 6 electrons in its outer shell. Hydrogen has 1. H wants 2 to fill its shell. All it needs is one more electron. Oxygen wants 8 electrons in it's outer shell. It needs 2 more. So 1 Oxygen atom and 2 Hydrogen atoms bond . Hydrogen and Oxygen share Electrons. But The Oxygen atom wants the Electrons more so they spend more time closer to Oxygen's valence shell.This is a polar covalent bond. It's molecules connect like Polar Ionic bonds do, Making a lot of water. Another way atoms bond is a Metallic bond. In this bond Multiple atoms rest in a sea of electrons.
I am grateful for Chemical bonds because without them there would just be a lot of atoms flying around.
The Periodic table and Matter
The Periodic Table list's all the Elements of the earth. It is categorized in many ways. You can read it from left to right by the Atomic number or number of Protons. On each element their is the Atomic number , Atomic mass( how much its mass is), Symbol ( like C for carbon) and Name. The parts across are called Periods, That is how the the table was named. Vertically they are called groups. They are also categorized in blocks. The blocks are the general shape of the electron cloud. The blocks are named with letters. They are s,d,p and f. Another way to categorize the Elements are by color. The different colors stand for Alkaline metals, Alkaline earth metals, Transition metals, Poor metals, Non-metals, halogens,Noble gases, Lanthanides and Actinides. Elements near the bottom are Radioactive and They have to be made in a lab. They symbols of some of the Atoms do not match up with their name. Like Au-gold,Ag-Silver,Fe-Iron, Na-Sodium, Pb-Lead and Cu-Copper . Here is why:
Gold,Silver,Copper,Iron,Sodium and lead got their Symbols from the Latin names for them.
Dmitri Mendeleev is usually associated with making the First Periodic table. But he did not make the first one Antoine-Laurent de Lavoisier a Frenchman made it. But it was not that good and it had very few elements. Mendeleev predicted elements in his table and it is way better than Antoine's. you can learn more about him in the History of Chemistry and Atoms section
Matter is something that takes up space. All matter is made out of Atoms. Matter is like weight but it measures how much of something there is not how much it weighs. Matter stays the same on every planet, But Weight changes. There are 5 main states of matter: Solid, Liquid, Gas,Colloid and plasma. Solid's molecules vibrate but don't really move around. Liquid's molecules move around. Gas's molecules move around very fast. The hotter matter is the faster the molecules in it move. Colloids are like a mix of solids and liquids. Its molecules are moving around slowly. Plasma is a gas with an electrical charge. Its Molecules are moving around Extremely fast. Most elements can be solids liquids or gases. Oxygen at room tempature is a gas. Gold at room temparure is a solid. But both these elements can be a heated or frozen to change their state of matter. There is also stuff that is not matter, it is called Dark/Anti matter. Scientist don't really now what is.It could be the stuff that is in black holes.
It is amazing to think about Dark matter. Scientist have many ideas for what it is made out of. Some think it is made out of something entirely new that is not matter or is made out of Atoms!
Fast fact!
Yesterday Scientists discovered how to change light into matter! In 1934 American/Russian Gregory Breit and American John Wheeler Proposed a way to change Light into matter. It is by Smashing-Shooting two Photons of light together. This would make an electron and a positron or anti-electron. A positron is a particle with the same mass as the electron but it has a positive charge. Positrons are not in Atoms. Some scientists think they are in Anti-Dark matter. Breit and Wheeler never thought it would be tried in a lab though. Some Scientists in the Imperial College London U.K. found out a way to do it. Here is the way: Scientists would speed up electrons close to the speed of light in a laser. Then they would shoot them at a gold piece to make extremely energy-full photons. After that the Scientist would use a tiny can made out of gold. They would shoot a high powered laser at the can making it release heat ,light and energy like a star. The scientists would shoot the energy-full photons at the can. The 2 photons from both places ( the can and the other photons ) collide and make electrons and protons.
Electronegativity and Moles
Electronegativity is how much force an atom has to attract an electron. Florine has the highest Electronegativity because it is so close to having a full valence shell and it dose not have that many electrons so the electrons are closer to the nucleus. The closer to the Nucleus electrons are the less they want to leave. Francium has the lowest Electronegativity because it has so many electrons and only on valence electron. O has a higher Electronegativity force than hydrogen that is why the electrons spend more time closer to Oxygen's valence shell.
Moles : the Mole is a number. Like a bakers dozen is 13 a mole is 602,000,000,000,000,000,000,000. It is sure a big number. If you had a mole of basketballs you could make a planet the size of the earth. Chemists use Moles to measure Atoms. Take a element say Oxygen. Oxygen's atomic mass is around 16. Turn that into 16 grams of Oxygen and you get one mole of Oxygen. The mole is also called Avogadro's number after the man who discovered it. He was an Italian, you can learn more about him in the History of Chemistry and Atoms section.
Fast fact!
Astronauts use a machine that brakes water up into Hydrogen and Oxygen. This is how they breath in the International Space station.
The History of Chemistry, Molecules and Atoms
Atoms H
For a long time people have wondered if there was a limit to cutting a thing in half. Say if you took a loaf of bread and cut it in half. Then you take one of those half's cut it in half and so on. Was there a particle so tiny you could not cut it? Democritus a Greek Philosopher thought their was. He called it the Atom from the Greek word Atomos for Indivisible. He thought this Around 441 BC.
No one really thought about Atoms Until the 17th century. In England a Chemist named John Dalton proposed that Atoms are the Smallest thing that still has its element's properties. Like if you divided a Atom of Gold it would not be Gold. It would be Protons,Neutrons and Electrons that were Separated. J.J. Thompson ( a British chemist) discovered electrons in 1897 with his experiment on Cathode rays. He thought of the Plum Pudding model. He thought the Atom was full with Positively charged stuff with Electrons stuck through it. In 1909 Ernest did a Experiment and proved the Plum Pudding model was wrong. Niels Bhor was a Danish physicist. He thought the electrons orbited the nucleus like planets in their own "energy levels". He also thought they could make a " Quantum jump " to another energy level. He called it the Bohr model. He invented it in 1913. Bohr also helped invent Quantum physics and the Atom bomb. Francis William Aston and Frederick Soddy discovered Isotopes and worked on Radioactivity. Werner Karl Heisenberg was a German who helped develop the Quantum physical model of the Atom. The modern view of the Atom. He also helped invent Quantum Physics. The view of the Atom today is a dense nucleus with electrons zipping around in a cloud on different shells. The view of the Atom might change in the future. So Democritus was wrong sort of. An Atom is the Smallest thing of an Element that still holds its elements Properties.
Fast fact!
Dalton also worked on color blindness and ( totally unrelated sorry :)the Sperm whale is loudest animal in the World.
Chemistry H
Aristotle another Greek Philosopher thought the world was made out of some sort of combination of these 4 elements Earth, Air, Fire and water. Everything that was not from the earth was made out of aether. People did not really work on it after that until the 15th century. During the time between Chemistry was called Alchemy. Alchemists were thought to have power in the Medieval ages. Alchemists main goals were to turn regular metals to gold and make the Potion of Eternal life. It had had some Properties of Chemistry but it had a lot of "magic" in it. Robert Boyle an Irish Chemist/Alchemist did Not believe in the Five-Element theory. He and some other scientists separated Chemistry from Alchemy. Chemistry was more scientific and real than alchemy. Robert Also wrote a book The Sceptical Chymist. He wrote about Chemical reactions. After him in 1774 Some Scottish Chemists Discovered Carbon dioxide CO2. Antoine-Laurent de Lavoisier discovered that Air was made out of other things like Hydrogen and Oxygen. He also discovered How Oxygen helps fire work. Lavoisier also made one of the first Periodic tables.In 1870 Mendeleev wrote two books under the same name: The principles of Chemistry. He said he had a dream where he saw all the Elements drawn out. Then he wrote his Table. Mendeleev also helped make Vodka. Justus von Liebig worked on Organic Chemistry. In 1959 Richard Feynman ( american ) challenged his friends to construct nanostuff. You can learn more about that in the nanotechnology part of this. He was born in 1918 and helped with making the Atom bomb. He died of cancer.
Molecule H
The Idea of Elements and atoms combining started all the way back with the 5 elements idea. Aristotle said everything on earth was a some sort of combination of four elements. Fire,Earth,Air and Water. In the 17th century Descartes thought atoms combine with hooks and eyes. In the 18th century French chemists said that a force draws certain atoms together. This force was called Chemical Affinity. August Wilhelm von Hofmann was the first to make ball and stick models of molecules. We now know that atoms bond into Molecules with valence electrons. You can learn more about that in the Chemical Bonds and Chemical equations part of this. In 2009 scientists took pictures of actual molecules!
I love History and I think that chemistry is cool so together it is Gargantuanly awesome!!!!
Cooking chemistry
Cooking is Chemistry. It is mixing ingredients, changing their temperature and changing their shape physically. I myself love cooking healthy foods. An example of cooking Chemistry is Baking bread. You mix the ingredients (an example of a mixture. In mixtures matter physically changes. With compounds Matter chemically changes). Then you let the dough set and the yeast makes the dough expand( this is a chemical reaction. The yeast eats the sugars in the wheat and release carbon dioxide. This makes the bread rise). After that you cook and heat it. This makes the water in it evaporate and the Molecules in the Dough move quickly. When it gets hot enough the yeast dies. Here is a experiment I tried :LINK . There is also chemistry in meat. There are protein molecules in the meat. When meat is cooked The proteins combine with the sugars in the meat and make a brown color. This is called the Maillard reaction after the guy who discovered it. It happens when the proteins on the out side get hotter than the inside. Proteins are coiled up before the meat is cooked. When it get hot enough proteins uncoil. Cooking it also makes it easier to digest and destroys harmful germs. There is also Chemistry in cheese. We make our own Cheese. Bacteria in the milk digest the milk sugar and makes lactic acid. When you add enzymes, rennet or Vinegar (like we do) they combine to the Lactic acid( a compound. Formula C3H6O3) and curdle the milk. Then they drain all the whey away and whats left is cheese! In Pickling Lactic acid stops bad bacteria from coming.
Fast fact!
waters name is dihydrogen oxide. Di-means two, so two hydrogen atoms and oxide oxygen Diffusion,Osmosis,Compounds and Nanotechnology
Diffusion
Diffusion is the movement of particles to areas of high concentration to areas of low concentration. Like when you but sugar in water. The sugar molecules diffuse away from the bottom where the sugar set. Molecules move on a concentration gradient. Molecules naturally move down a concentration gradient(Moving from high concentration to low concentration). They keep moving until it is equal ( equilibrium ). Molecules do not stop moving at equilibrium, But when they move it dose not mix it up more. Molecules always are moving or vibrating. Diffusion is caused by the constant random motion of molecules. The Faster this motion is the faster diffusion happens. The hotter something is the faster the molecules move. So Diffusion happens fastest in gases then liquids and last solids. Diffusion is in lots of subjects. Its used in lots of technologies like Water purification. Diffusion happens with Energy too. If you heat one end of a metal then the heat would diffuse to the other end moving down a concentration gradient. The metal would also let out thermal radiation. . A type of Diffusion.Visible light is Thermal Radiation. When something gets the right temperature some energy diffuses into visible light . Electricity works with diffusion to. Electrons move from areas of high electron concentration to areas of low electron concentration. Molecular diffusion also makes nutrients and other molecules move around cell membranes. That is called Osmosis. Ideas can also diffuse in cultural diffusion but that's not chemistry.
Osmosis
Osmosis is (like I wrote above) the movement of molecules across a semi-permeable membrane into and out of cells.When a animal cell is in a lot of water (Hypotonic) it takes as much water as it can until it bursts. If it is in to much salt ( Hypertonic ) it will dry up. That is why we need to watch are intake of salt and water.
Compounds
Compounds are made when atoms combine in chemical reactions. Like water( H2O) and salt( NaCl). Compounds don't have to look like their original elements. When the atoms combine they go trough a chemical change.
Nanotechnology
Nanotech is the technology of managing very small things. Things under 100 Nanometers. A Nanometer is 1 billionth of a meter. Nanometers are Incredibly small but one Nanometer is bigger than a atom. This tech deals with atoms and molecules. Richard Feynman an American Physicist said that you could build a motor 1/64 of an inch long or to build a page of a book 1/25,000 the size of a regular page. The Motor was made in 1960 and the page was made in 1985. They used a scanning electron microscope to read the page. You can learn more about Microscopes here. By changing things at the Atomic level Chemists could change an elements properties. Like if you could add or take away Protons, Neutrons and electrons you could change lead into gold! Chemists have not exactly gotten there yet but they might in the future. Nanotech will be big in the future if you ask me. Nanotechnology can be used to make Nuclear fusion on earth real. You can learn more about that in the The Nuclear weapon, Radioactivity and Nuclear power part of this. Nano-scientists want to build nanobots. Teeny,tiny weeny robots. They could program these robots to do plenty of good things. Like they could be used to eat gases that contribute to global warming like Methane. They could be used to go in your bloodstrem without destroying anything but dangerous germs like cancer. They could be used to destroy all the Ticks and Mosquitoes in the world. They Could be used to Destroy Pollution. They could be used to play tiny soccer games the you could watch with a electron microscope. They could be used to stop fire. They could be used to repair buildings. They could be used to take pictures of Neutrinos ( learn more about these in the Quantum physics part of this) or other tiny particles like electrons. Nanobots will be useful. Nanotech could make the world a better place to live. But there might be some downsides. Nanobots could be used a weapons and viruses and destroy the world.This is called the grey goo problem.Here is the theory: People build a nanobot that duplicates every 6 or 7 minutes. After 2 days or so the nanobots will weigh more than the planet!.Here are some nanothings that have already been made: Nanotubes: These tubes are made out of carbon molecules. Nanotubes are one molecule thick black tubes.They are used in microscopy ,Nanofiber:these are nano-sized fibers that might be used in stitching. They leave no scar. ,Nanomesh:Nanomesh is a web of lots nano-sized strings. They may be used in filtering air. ,Nanoshells:Nanoshells are tiny balls made out of metal that absorb and reflect every wavelength. They might be used for eyeglasses. ,Nanowires:these are super super thin wires. They can be used in electricity. ,Nanobalance:these are nano sized scales. They can weigh atoms! and the Nanogutiar:this is a super small guitar. . Eric Drexler was and is really important to Nanotechnology. He wrote many books on the subject. He founded a non-profit think tank that teaches people about Nanotechnology. He also popularized the term Nanotechnology.
sources: Brainpop,Wikipedia, Ted-Ed , The elements app, www.eurekalert.org,www.exploratorium.edu/cooking/bread/bread_science.html, http://www.ck12.org , What your Fifth grader needs to Know and Khan academy
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