Science Information

 Matter : Elements , Compounds and Mixtures Classification of Matter    1.Elements    2.Compounds    3.Mixtures Element Definition: Elements – Elements constitute the simplest chemical substances in which all the atoms are exactly the same. Compound Definition: Compounds – Compounds are chemical substances made up of two or more elements that are chemically bound together in a fixed ratio. What is a Compound? When two or more elements chemically combine in a fixed ratio by mass, the obtained product is known as a compound. Compounds can be defined as substances consisting of 2 or more different types of elements in a fixed ratio of its atoms. When the elements combine, some individual property of the elements is lost and the newly formed compound has new properties. Chemical Formula : Compounds are represented by their chemical formula. A chemical formula is a symbolic representation of the proportions of atoms that constitute a particular chemical co...

 Matter : definition and 5 states of matter A glass holds H20 in three states of matter: ice (solid), water (liquid) and vapor (gas).  Matter is the "stuff" that makes up the universe — everything that takes up space and has mass is matter.  All matter is made up of atoms, which are in turn made up of protons, neutrons and electrons.  Atoms come together to form molecules, which are the building blocks for all types of matter, according to Washington State University. Both atoms and molecules are held together by a form of potential energy called chemical energy. Unlike kinetic energy, which is the energy of an object in motion, potential energy is the energy stored in an object.  The Five States Of Matter There are four natural states of matter: Solids, liquids, gases and plasma. The fifth state is the man-made Bose-Einstein condensates. Solids In a solid, particles are packed tightly together so they don't move much. The electrons of each atom are constantly i...

What Is an Atom? The image of an atom. It consists of a nucleus in its center and the electrons are revolving in circular orbits. Atoms are the basic units of matter and the defining structure of elements. The term "atom" comes from the Greek word for indivisible, because it was once thought that atoms were the smallest things in the universe and could not be divided. We now know that atoms are made up of three particles: protons, neutrons and electrons — which are composed of even smaller particles, such as quarks. Atoms were created after the Big Bang 13.7 billion years ago. As the hot, dense new universe cooled, conditions became suitable for quarks and electrons to form. Quarks came together to form protons and neutrons, and these particles combined into nuclei. This all took place within the first few minutes of the universe's existence, according to CERN. It took 380,000 years for the universe to cool enough to slow down the electrons so that the nuclei could captur...

 Molecules Molecule, a group of two or more atoms that form the smallest identifiable unit into which a pure substance can be divided and still retain the composition and chemical properties of that substance. The image of a molecule.   Several methods of representing a molecule's structure. In Lewis structures, element symbols represent atoms , and dots represent electrons surrounding them. A pair of shared electrons (covalent bond) may also be shown as a single dash. The ball-and-stick model better illustrates the spatial arrangement of the atoms . For aromatic compounds, the Kekulé structure is common, in which each bond is represented by a dash, carbon atoms are implied where two or more lines meet, and hydrogen atoms are usually omitted. Bond-line formulas, similar to the Kekulé structure, are often used for complex nonaromatic organic compounds. Sugars are often drawn as Fischer projections, in which the carbon “backbone” is drawn as a straight vertical line, with carbo...