{"id":2370,"date":"2020-12-03T09:17:55","date_gmt":"2020-12-03T03:47:55","guid":{"rendered":"https:\/\/cbselibrary.com\/?p=2370"},"modified":"2020-12-03T10:32:16","modified_gmt":"2020-12-03T05:02:16","slug":"definition-atom-molecule","status":"publish","type":"post","link":"https:\/\/cbselibrary.com\/definition-atom-molecule\/","title":{"rendered":"What is the Definition of Atom and Molecule"},"content":{"rendered":"
Atom:<\/strong><\/span> People also ask<\/b><\/p>\n Molecules:<\/b><\/strong><\/span> 1. Molecules of elements <\/b><\/strong><\/span> 2. Molecules of compounds<\/b><\/strong><\/span> Molecules of some compounds<\/b><\/strong>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0<\/span><\/p>\n Compound<\/strong><\/p>\n<\/td>\n Water<\/p>\n<\/td>\n 14:3<\/p>\n<\/td>\n<\/tr>\n Carbon dioxide<\/p>\n<\/td>\n 3:8<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Atomicity <\/b><\/strong><\/span> Atomicity of some common elements.<\/b><\/strong><\/span><\/p>\n Type of element<\/b><\/strong><\/p>\n<\/td>\n Non-metal<\/p>\n<\/td>\n Argon<\/p>\n<\/td>\n Neon<\/p>\n<\/td>\n Diatomic<\/p>\n<\/td>\n<\/tr>\n Diatomic<\/p>\n<\/td>\n<\/tr>\n Nitrogen<\/p>\n<\/td>\n Diatomic<\/p>\n<\/td>\n<\/tr>\n Phosphorus<\/p>\n<\/td>\n Polyatomic<\/p>\n<\/td>\n<\/tr>\n Metals<\/p>\n<\/td>\n Sodium<\/p>\n<\/td>\n Monoatomic<\/p>\n<\/td>\n<\/tr>\n Aluminium<\/p>\n<\/td>\n Monoatomic<\/p>\n<\/td>\n<\/tr>\n Monoatomic<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":" What is the Definition of Atom and Molecule\u00a0 Atom: All the matter is made up of atoms. An atom is the smallest particle of an element that can take part in a chemical reaction. Atoms of most of the elements are very reactive and do not exist in the free state. They exist in combination … Read more<\/a><\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":""},"categories":[84],"tags":[1024,1028,1025,1027,1026],"yoast_head":"\n
\nAll the matter is made up of atoms. An atom<\/strong> is the smallest particle of an element that can take part in a chemical reaction. Atoms of most of the elements are very reactive and do not exist in the free state. They exist in combination with the atoms of the same element of another element.
\nAtoms are very, very small in size. The size of an atom is indicated by its radius which is called \u2018atomic radius\u2019. Atomic radius is measured in \u2018nanometres<\/strong>\u2019. The symbol of a nanometre is nm.
\n1 nanometre = \u00a0\\(\\frac { 1 }{ { 10 }^{ 9 } } \\) metre
\nor\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 1 nm =\u00a0 \u00a0\\(\\frac { 1 }{ { 10 }^{ 9 } } \\) m
\nor \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 1 nm = 10\u20139<\/sup> m
\nHydrogen atom is the smallest atom of all. They cannot be viewed by simple optical microscopes. However, through modern techniques such as scanning tunneling microscope it is possible to produce magnified images of surfaces of elements showing atoms.<\/p>\n\n
\nA combination of atoms is called a molecule<\/strong>. The forces which hold the atoms together in a molecule are called covalent bonds.
\nA molecule is the smallest particle of a substance which has the properties of that substance and can exist in the free state.
\nThere are two types of molecules.<\/p>\n
\nThe molecule of an element contains two (or more) similar atoms chemically combined together.
\nExample: \u00a0 \u00a0<\/b><\/strong>A molecule of hydrogen element contains 2 hydrogen atoms combined together, and it is written as H2<\/sub>.<\/p>\n
\nThe molecule of a compound contains two (or more) different types of atoms chemically combined together.
\nExample: \u00a0 \u00a0<\/b><\/strong>Hydrogen chloride is a compound. The molecule of hydrogen chloride (HCl) contains two different types of atom. Hydrogen(H) and chlorine atom (Cl)<\/p>\n\n\n
\n \n Combining elements<\/strong><\/td>\n Formula<\/strong><\/td>\n Ratio by mass<\/strong><\/td>\n<\/tr>\n \n \n Hydrogen and oxygen<\/td>\n H2<\/sub>O<\/td>\n 1:8<\/td>\n<\/tr>\n \n \u00a0Ammonia<\/td>\n Nitrogen and Hydrogen<\/td>\n NH3<\/sub><\/td>\n \n \n \n Carbon and Oxygen<\/td>\n CO2<\/sub><\/td>\n \n
\nThe number of atoms present in one molecule of an element is called its atomicity<\/strong>.
\nExample: \u00a0 \u00a0<\/b><\/strong>Noble gases (helium, neon, argon, krypton, etc.) have one atom each in their molecules such as He, Ne, Ar and Kr. So, the atomicity of noble gases is 1.
\nExample: \u00a0 \u00a0<\/b><\/strong>Hydrogen (H2<\/sub>), nitrogen (N2<\/sub>), oxygen (O2<\/sub>), chlorine (Cl2<\/sub>), bromine (Br2<\/sub>), and iodine (I2<\/sub>), all have 2 atoms each in their molecules. So, the atomicity of hydrogen, nitrogen, oxygen, chlorine, bromine and iodine is 2 each.<\/p>\n\n\n
\n \n Name<\/b><\/strong><\/td>\n Symbol<\/b><\/strong><\/td>\n Atomicity<\/b><\/strong><\/td>\n<\/tr>\n \n \n Helium<\/td>\n He<\/td>\n Monoatomic<\/td>\n<\/tr>\n \n <\/td>\n \n Ar<\/td>\n Monoatomic<\/td>\n<\/tr>\n \n <\/td>\n \n Ne<\/td>\n Monoatomic<\/td>\n<\/tr>\n \n <\/td>\n Hydrogen<\/td>\n H2<\/sub><\/td>\n \n \n <\/td>\n Chlorine<\/td>\n Cl2<\/sub><\/td>\n \n \n <\/td>\n \n N2<\/sub><\/td>\n Diatomic<\/td>\n<\/tr>\n \n <\/td>\n Oxygen<\/td>\n O2<\/sub><\/td>\n \n \n <\/td>\n \n P4<\/sub><\/td>\n Tetratomic<\/td>\n<\/tr>\n \n <\/td>\n Sulphur<\/td>\n S8<\/sub><\/td>\n \n \n \n \n Na<\/td>\n Monoatomic<\/td>\n<\/tr>\n \n <\/td>\n Iron<\/td>\n Fe<\/td>\n \n \n <\/td>\n \n Al<\/td>\n \n \n <\/td>\n Copper<\/td>\n Cu<\/td>\n \n