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Before the 20th century, the term matter included ordinary matter composed of atoms and excluded other energy phenomena such as light or sound. This concept of matter may be generalized from atoms to include any objects having mass even when at rest, but this is ill-defined because an object's mass can arise from its (possibly massless) constituents' motion and interaction energies. Thus, matter does not have a universal definition, nor is it a fundamental concept in physics today. Matter is also used loosely as a general term for the substance that makes up all observable physical objects.[1][2] All the objects from everyday life that we can bump into, touch or squeeze are composed of atoms. This atomic matter is in turn made up of interacting subatomic particles—usually a nucleus of protons and neutrons, and a cloud of orbiting electrons.[3][4] Typically, science considers these composite particles matter because they have both rest mass and volume. Definition Common definition Quarks Related: Assets

Are We Really All Made of Stars? | Cosmos, Moby’s Song ‘We Are All Made of Stars’, Universe & Solar System | Life's Little Mysteries The theory that everyone and everything on Earth contains minuscule star particles dates back further than Moby's popular 2002 song "We Are All Made of Stars." In the early 1980s, astronomer Carl Sagan hosted and narrated a 13-part television series called "Cosmos" that aired on PBS. On the show, Sagan thoroughly explained many science-related topics, including Earth's history, evolution, the origin of life and the solar system. "We are a way for the universe to know itself. Some part of our being knows this is where we came from. His statement sums up the fact that the carbon, nitrogen and oxygen atoms in our bodies, as well as atoms of all other heavy elements, were created in previous generations of stars over 4.5 billion years ago. "All organic matter containing carbon was produced originally in stars," Impey told Life's Little Mysteries. How star stuff got to Earth When it has exhausted its supply of hydrogen, it can die in a violent explostion, called a nova. Cosmic connections

What Is Caustic Soda and Where Can You Get It? Key Takeaways: Caustic Soda Caustic soda is one of the common names for sodium hydroxide (NaOH).It is also known as lye, although lye may refer to either potassium hydroxide or sodium hydroxide.Pure caustic soda is sold for making candles or soap.Impure caustic soda is found in drain cleaner.Because lye is used to make illegal drugs, it's harder to buy large quantities than in the past. However, small containers are available in stores and online. Uses of Caustic Soda or Lye Lye is used for soap making, candle making, homemade biodiesel, frosting glass, making several foods, and for chemistry experiments. How To Get Caustic Soda or Lye It's much harder to get hold of lye than it used to be in the past. drain cleaner (check the label) - e.g., Roebic Crystal Drain Cleaner, sold as Lowessodium hydroxide from an online chemical supply storesoap making storecandle making storebiodiesel supply store Helpful Tips Since it's relatively hard to get hold of this chemical, you may need to buy in bulk.

Mulungu Bark and Mulungu Powder Mulungu Mulungu is a medium-sized, well-branched tree that grows 10-14 m high. It produces many pretty, reddish-orange flowers (pollinated by hummingbirds) at the ends of the tree's many branches. Several Erythrina tree species are used by indigenous peoples in the Amazon as medicines, insecticides, and fish poisons. In both North and South American herbal medicine, Mulungu is considered to be an excellent sedative to calm agitation and nervous coughs and to treat other nervous system problems including insomnia and anxiety. Mulungu is not very widely known or used in North America; mostly appearing as an ingredient in only a few herbal formulas for anxiety or depression.

Composition of the human body The main elements that compose the human body are shown from most abundant (by mass) to least abundant. The elemental composition of the human body can be looked at from the point of view of either mass composition, or atomic composition. To illustrate both views, the adult male human body is approximately 57% water, and water is 11% hydrogen by mass but 67% by count of atoms (i.e. 67 atomic percent). Thus, most of the mass of the human body is oxygen, but most of the atoms in the human body are hydrogen atoms. Both mass-composition and atomic composition figures are given below (see pie graphs and table). Body composition may also be analyzed in terms of molecular type (e.g., water, protein, connective tissue, fats (or lipids) apatite (in bones), carbohydrates (such as glycogen and glucose) and DNA. Major, minor and trace elements[edit] Pie charts of typical human body composition by percent of mass, and by percent of atomic composition (atomic percent). Elemental composition list[edit]