ATOM
STRUCTURE
DEVELOPMENT :
MODELS
Law of Conversation of Mass
Law of Definite Portion
Indivisible Matter
JJ Thompson's Plum Pudding Model
Gold Foil Experiment
Billiard Ball Model of Atom
Cations and Anions
Structure of Atom
The gold-foil experiment revealed that the atom is made up of a tiny, massive, positively charged nucleus with negatively charged electrons located far away from the nucleus.
Using a Crookes, or cathode ray, tube, Thomson discovered the electron. Cathode rays were shown to be negatively charged by him.
The rule of conservation of mass and the law of definite proportions, according to Dalton, might be explained using the concept of atoms.
Periodic Table of Elemnets
The law of definite proportions, often known as Proust's law or the law of constant composition, holds that a chemical compound's component components are always present in a set ratio (by mass) regardless of its source or method of creation. The Law of Definite Proportions states that no matter how much water there is, whether it's 2 moles or 54 grams, the ratio of hydrogen to oxygen by weight will always be the same, just as the egg:sugar:butter ratio in chocolate cake should be stable.
The notion that the mass of any closed system exposed to no external influences remains constant regardless of changes in shape; the principle that matter cannot be generated or destroyed. Also known as the law of conservation of mass or the law of conservation of matter. The law of conservation of mass holds that no mass is generated or lost during a chemical process. When coal is burnt, for example, the carbon atom transforms into carbon dioxide. The mass of a carbon atom does not change as it transitions from a solid to a gas.
The building components of matter are indivisible. Leucippus and Democritus wrote about this concept in the fifth century BCE. The Greeks termed these particles atomos, which means "indivisible," from whence the current word "atom" is derived. Democritus thought that atoms were uniform, solid, hard, incompressible, and indestructible, and that they travelled in an endless number of directions across empty space until they were stopped. The varied qualities of matter were defined by differences in atomic form and size. Atoms existed in Democritus' philosophy not just for substance, but also for attributes like perception and the human soul.
PROTON a stable subatomic particle found in all atomic nuclei and having a positive electric charge equal to that of an electron but with the opposite sign. ELECTRON a stable subatomic particle with a negative electrical charge that can be found in all atoms and serves as the major carrier of electricity in solids. NEUTON all atomic nuclei except those of common hydrogen include a subatomic particle with nearly the same mass as a proton but no electric charge.
Ions are atoms or molecules with one or more valence electrons acquired or lost, resulting in a net positive or negative charge. A cation is a chemical species with more protons than electrons, and therefore a positive charge, whereas an anion is a chemical species with more electrons than protons, and so a negative charge. Anions and cations are the two types of plant nutrients that occur in the soil. What exactly are they? Most molecules in natural systems have a positive or negative charge, and this charge difference is what keeps us all alive by driving chemical reactions.
The table of Dmitri Mendeleev is significant because it shows how elements with comparable physical and chemical characteristics appear at regular intervals (that is, periodically). The periodic table is used by scientists to rapidly refer to information about an element, such as its atomic mass and chemical symbol. Scientists may also see patterns in element characteristics like electronegativity, ionization energy, and atomic radius thanks to the periodic table's layout.
