Another awesome experiment.

Organic Chemistry

What is Organic Chemistry?

Organic chemistry is the branch of chemistry that deals with organic molecules. An organic molecule is one which contains carbon, and these molecules can range in size from simple molecules to complex structures containing thousands of atoms! Although carbon is present in all organic compounds, other elements such as hydrogen (H), oxygen (O), nitrogen (N), sulphur (S) and phosphorus (P) are also common in these molecules.

Until the early nineteenth century, chemists had managed to make many simple compounds in the laboratory, but were still unable to produce the complex molecules that they found in living organisms. It was around this time that a Swedish chemist called Jons Jakob Berzelius suggested that compounds found only in living organisms (the organic compounds) should be grouped separately from those found in the non-living world (the inorganic compounds). He also suggested that the laws that governed how organic compounds formed, were different from those for inorganic compounds. From this, the idea developed that there was a ’vital force’ in organic compounds. In other words, scientists believed that organic compounds would not follow the normal physical and chemical laws that applied to other inorganic compounds because the very ’force of life’ made them different.

This idea of a mystical ’vital force’ in organic compounds was weakened when scientists began to manufacture organic compounds in the laboratory from non-living materials. One of the first to do this was Friedrich Wohler in 1828, who successfully prepared urea, an organic compound in the urine of animals which, until that point, had only been found in animals. A few years later a student of Wohler’s, Hermann Kolbe, made the organic compound acetic acid from inorganic compounds. By this stage it was acknowledged that organic compounds are governed by exactly the same laws that apply to inorganic compounds. The properties of organic compounds are not due to a ’vital force’ but to the unique properties of the carbon atom itself. Organic compounds are very important in daily life. They make up a big part of our own bodies, they are in the food we eat and in the clothes we wear. Organic compounds are also used to make products such as medicines, plastics, washing powders, dyes, along with a list of other items.

Density

An important property of any material is its density, defined as its mass per unit volume. A homogeneous material such as ice or iron has the same density throughout. We use (the Greek letter rho) for density. If a mass m of homogeneous material has volume V, the density is

Two objects made of the same material have the same density even though they may have different masses and different volumes. That’s because the ratio of mass to volume is the same for both objects. 

The SI unit of density is the kilogram per cubic meter . The cgs unit, the gram per cubic centimeter is also widely used:

Densities of Some Common Substances

Fluids

A fluid is any material that can flow and that takes the shape of its container. Liquids and gases are fluids.For example, you could fill a fishbowl with water or with air.Each would take the shape of the bowl. Fluids can flow because the particles in fluids move past one another easily.

Fluid statics -the study of fluids at rest in equilibrium situations. Like other equilibrium situations, it is based on Newton’s first and third laws.

Fluid dynamics - the study of fluids in motion.

Stars

Composition of Stars

To learn what stars are made of, astronomers study the light from stars. When you look at white light through

a glass prism, you see a rainbow of colors called a spectrum (plural, spectra). The spectrum consists of millions of colors, including red, orange, yellow, green, blue, and violet. Astronomers use an instrument called a spectroscope to separate a star’s light into a spectrum. The spectrum gives astronomers information about the composition and temperature of a star.

Types of Spectra

A hot, solid object, such as the glowing wire inside a light bulb, gives off a continuous spectrum. A continuous spectrum shows all of the colors. However, hot gases emit only certain wavelengths of light, or colors. When a chemical element emits light, only some colors in the spectrum show up. All of the other colors are missing. The colors that appear are called emission lines. Every element has a unique set of bright emission lines that act like a fingerprint for that element.

Types of Stars

10 Amazing Science Experiments you can do with Eggs

Watch these 10 amazing science experiments you can do with eggs. Very wow! And very simple to do. 

Michael Faraday

Michael Faraday (1791-1867). He was born on September 22, 1791 near London. He was the son of a black smith and at an early age was an apprentice to a bookbinder. He studied science in his leisure time and in 1812 he listened to the lectures of the chemist, Sir Humphrey Davy, for whom he worked as an assistant later.

Faraday discovered the principle of electromagnetic induction in 1831. His work on electrochemistry led to the discovery of the relationship between electricity and the valence of an element. This was the first clue to the electron. Faraday was the first to liquefy gases and distill benzene from fish oil. He died on August 25, 1867.

Friction

Friction is the resistance or opposition to slide one body over another. When we walk there is friction between the ground and the soles of our shoes. When a car runs, there is friction between the tires and the ground.

Uses of Friction
Friction is useful in many ways. If there is no friction we cannot attach things together. The nails and screws will not work and we cannot have houses. Dresses cannot be sewed. Even trees cannot stand and the roots cannot hold to the ground. Machines will not work without friction. The parts of machines will just slide and slip and nothing can be done.

Ways of Increasing Friction
Friction may be increased by scattering sand and pebbles on the road during rainy days when the road is slippery. This is especially true in cold countries where ice and snow cover the road. Chains are attached to the wheels of vehicles to increase friction. Shoes of runners (athletes) have spikes. Tires of automobiles and trucks have designs curved on them. The soles of rubber shoes have carved designs not just to make them look better but to increase friction.

Ways of Reducing Friction
Friction may be reduced by (1) the use of oil or grease (2) making the surface smooth by planning, filing, sandpapering or scrubbing as in floors (3) streamlining. Jet and airplanes nowadays have cambered wings and well-shaped bodies. Cards have rounded tops and nicely curved backs and fronts. Ships are elongated in shape. All these are done to reduce friction and enable the vessels to move faster in air or water. (4) Using ball or roller bearings. Roller skates make a good example. Many machines have ball bearings.

Comet on October 19

Be very excited. On October 19th something ridiculous is going to happen. A rare comet from the Oort Cloud at the edge of our solar system is going to fly past NASA’s MAVEN robot as it orbits around Mars.  It’ll be so close that they’re going to postpone work on Mars and study the comet for five days.

This will be the closest a comet’s ever gotten to Mars in human history and it’s coming from so far away that it’s likely going to have a lot of material we otherwise couldn’t find in the solar system very easily.

The chances of this happening are far less than one in a million.

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Repost from antikythera-astronomy. 

ALBERT EINSTEIN

Albert Einstein (1879–1955) was born in Germany. When he was in high school, his father’s business failed and his family moved to Milan, Italy. Einstein had to stay behind because German law required compulsory military service after finishing high school. Einstein wanted to join his family in Italy. His high school mathematics teacher wrote a letter saying that Einstein could have a nervous breakdown without his family and also that there was nothing left to teach him. Eventually, Einstein was asked to leave the school because of his disruptive behavior. Popular folklore says he left because of poor grades in Latin and Greek, but
his grades in those subjects were fine.

Einstein was visiting the United States when Hitler came to power, so he accepted a position at the Institute for Advanced Study in Princeton, becoming a U.S. citizen in 1940. Although a lifelong pacifist, he wrote a letter to President Roosevelt warning of ominous advances in German nuclear research. This led to the creation of the Manhattan Project, which developed the atomic bomb and tested it in New Mexico in 1945.

Atomic Number and Mass Number

The atomic number of an atom equals the number of protons in its nucleus. The atomic number is also the number of electrons that surround the nucleus of a neutral atom. For example, the atomic number of carbon is 6, which means that a neutral carbon atom has six protons and six electrons. Because the number of protons in an atom does not change, the atomic number of a particular element is always the same—all carbon atoms have an atomic number of 6.

The mass number of an atom is the sum of its protons and neutrons. Not all carbon atoms have the same mass number, because, even though they all have the same number of protons, they do not all have the same number of neutrons. For example, 98.89% of naturally occurring carbon atoms have six neutrons—giving them a mass number of 12—and 1.11% have seven neutrons—giving them a mass number of 13. These two different kinds of carbon atoms and are called isotopes. Isotopes have the same atomic number (i.e., the same number of protons), but different mass numbers because they have different numbers of neutrons. The chemical properties of isotopes of a given element are nearly identical

What is Calorimetry?

Calorimetry is the art of measuring energy.  For example, determining how many calories are in a cheeseburger is done with a device called a “bomb calorimeter.”  A sample of the food is burned in a closed container that is surrounded by water. The energy content of the food is determined from the temperature increase of the water jacket that surrounds the combustion chamber.