Chemistry-Trip - online Chemistry learning

 IONIC OR ELECTROVALENT BONDS: Definition of ionic or Electrovalent bond: It formed by electrostatic attraction between positive and negative ions, this is achieve by the transfer of single or more electrons to the atoms or atomic groups. • Atom loses or gain electrons to gain nearest Nobel gas configuration. • Ionic bonds are most likely to formed by when compounds have low ionization energies will react with elements have higher electronegative and electron affinity. • Generally: Group IA and IIA react with VI A or VII A. • Mostly metals and non metal react to form the ionic compounds. Reaction of sodium with chloride(example of electrovalent compounds): Na +Cl ---->NaCl In this reaction sodium loses a single electron to achieve neon ( Nobel gas) configuration. The energy it required is 496kJ/mol Where as the chlorine attain a electron and converted to chloride ion it is trying to get electronic configuration of argon . The energy it releases is 349kJ/mol IONIC  CRYSTAL ST

  Covalent Bond: Definition: covalent Bond is form by the mutual sharing of electrons between two atoms. Each atom contributes one electron from its valence electron shell to the shared pair of electrons. According to lewis ,paring of electrons should lead to nobel gas configuration.the mutual sharing of elecrrons pair is is considered to be possesed by boththe atoms in common,which will contributes to the electronic configuration of each atom of the molecule. in a covalent Bond sharing of electron pair is energetically favourable energy is liberated when two atoms form a covalent bond. Shared pair of electrons lie between nuclei of two atoms so electron attracted by two nuclei.where as electron repel each other as well as electroms also repel each other. The repulsion is offset by attraction of electron and nuclei. Nuclei shared electron pair is held together by this net attractive forces. Lewis Structure: shared electron pair is represented by the dot or line.Lewis structure use only

Solids: solids are substance s which has rigid, have definite shape and definite volume  Typeses of Solids: There are three types of solid  crystalline polycrystalline amorphous solids crystalline Solids: This is the substance in which molecules and atoms  have a definite shape, arrangeed in definite three dimensional manner. whole volume -periodic NaCl                          Amorphous solids. this re the solids in which molecules and atoms ,ions do not have regular arrangement. example of amorphous solids: rubber, plastic, glue, glass. Many crystalline solids converted to amorphous solids by cooling them rapidly after melting. amorphous solids do not have sharp melting points.they have small range of regularity but large range of orderly arrangement in amorphous solids do not exist  non periodic poly crystalline: composed of many crystallite of varying shape and orientation. each grain -periodic Properties/characteristics of crystalline solids. Melting points: crystalline can be ide