Ekarahmadani

Narration and dialogue The Development of Atomic Theory Since the early 1900s scientists have known that the material-forming atoms are made up of tiny nuclei surrounded by electrons. The core is made up of particles that look tight. In this article the development of atomic theory we will discuss the development of the theory about the atom based on the discovery of the findings that have been done by the physicists. The Dalton Atomic Model John Dalton (1766-1844), a British scientist supported by the results of his experiments developed the atomic concept of Democritus which later revealed the theory of the atom. Broadly speaking Dalton atomic theory can be summed up as follows: Atoms are the smallest part of a substance that can not be divided again. The atoms of a particular substance have the same properties. The atoms of certain elements can not be transformed into atoms of other elements. Two or more atoms can unite (react) to form molecules. Teacher: All students, do you n...

What is Acid Rain? Acid rain refers to a mixture of deposited material, both wet and dry, coming from the atmosphere containing more than normal amounts of nitric and sulfuric acids. Simply put, it means rain that is acidic in nature due to the presence of certain pollutants in the air due to cars and industrial processes. It is easily defined as rain, fog, sleet or snow that has been made acidic by pollutants in the air as a result of fossil fuel and industrial combustions that mostly emits Nitrogen Oxides (NOx) and Sulfur Dioxide (SO2). Acidity is determined on the basis of the pH level of the water droplets. Normal rain water is slightly acidic with a pH range of 5.3-6.0, because carbon dioxide and water present in the air react together to form carbonic acid, which is a weak acid. When the pH level of rain water falls below this range, it becomes acid rain. When these gases react with water molecules and oxygen among other chemicals found in the atmosphere, mild acidic chemical ...

CHEMISTRY I: ATOMS AND MOLECULES Atoms Most of the Universe consists of matter and energy. Energy is the capacity to do work. Matter has mass and occupies space. All matter is composed of basic elements that cannot be broken down to substances with different chemical or physical properties. Elements are substances consisting of one type of atom, for example Carbon atoms make up diamond, and also graphite. Pure (24K) gold is composed of only one type of atom, gold atoms. Atoms are the smallest particle into which an element can be divided. The ancient Greek philosophers developed the concept of the atom, although they considered it the fundamental particle that could not be broken down. Since the work of Enrico Fermi and his colleagues, we now know that the atom is divisible, often releasing tremendous energies as in nuclear explosions or (in a controlled fashion in) thermonuclear power plants. Subatomic particles were discovered during the 1800s. For our purposes we will concentra...