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Author: misamaliraza94

  • Covalent Bond

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    A covalent bond is formed when pairs of electrons are shared between two atoms. It is primarily formed between two same nonmetallic atoms or between nonmetallic atoms with similar electronegativity. Lewis Dot Structure Lewis structures are also known as Lewis dot structures or electron dot structures.These are basically diagrams with the element’s symbol in the centre.…

  • Ionic Bond

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    Ionic bonding involves the transfer of valence electron/s, primarily between a metal and a nonmetal. The electrostatic attractions between the oppositely charged ions hold the compound together.Ionic compounds: Are usually crystalline solids (made of ions) Have high melting and boiling points Conduct electricity when melted Are mostly soluble in water and polar solvents

  • Covalent Bonding

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    Difficulty of Carbon to Form a Stable Ion To achieve the electronic configuration of the nearest noble gas, He, if the carbon atom loses four of its valence electrons, a huge amount of energy is involved. C4+ ion hence formed will be highly unstable due to the presence of six protons and two electrons. If the…

  • Introduction

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    Chemical substances containing carbon are referred to as carbon compounds. Except for hydrogen, there are more carbon compounds than any other chemical element. Compounds of carbon with double bonds and triple bonds are called as unsaturated compounds while those with carbon-carbon single bonds are called saturated compounds.

  • The Why Questions

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    Electronic Configuration Group 1 elements – Alkali metals Element Electronic Configuration  Lithium(Li) 2,1 Sodium(Na) 2,8,1 Potassium(K) 2,8,8,1 Rubidium(Rb) 2,8,18,8,1 Group 2 elements – Alkaline earth metals Element Electronic Configuration  Beryllium(Be) 2,2 Magnesium(Mg) 2,8,2 Calcium(Ca) 2,8,8,2 Stronium(Sr) 2,8,18,8,2 How Do Metals and Nonmetals React Metals lose valence electron(s) and form cations.Non-metals gain those electrons in their…

  • Refining of Metals

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    Refining of metals – removing impurities or gangue from crude metal. It is the last step in metallurgy and is based on the difference between the properties of metal and the gangue. Electrolytic Refining Metals like copper, zinc, nickel, silver, tin, gold etc., are refined electrolytically.Anode: impure or crude metalCathode: a thin strip of pure metalElectrolyte: aqueous solution of metal…

  • Extracting Metals in Middle of Reactivity Series

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    Calcination is a process in which ore is heated in the absence of air or air might be supplied in limited quantity. Roasting involves heating of ore lower than its melting point in the presence of air or oxygen. Calcination involves thermal decomposition of carbonate ores. Smelting – it involves heating the roasted or calcined ore…

  • Reaction of Metals with Bases

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    The base has a bitter taste and a slippery texture. A base dissolved in water is called an alkali. When chemically reacting with acids, such compounds produce salts. Bases are known to turn blue on red litmus paper. Base+metal → salt+hydrogen2NaOH(aq)+Zn(s) → Na2ZnO2(aq)+H2(g)2NaOH(aq)+2Al(s)+2H2O(l) → 2NaAlO2(aq)+2H2(g) Extraction of Metals and Non-Metals Applications of Displacement Reaction Uses…

  • Roasting and Others

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    Converts sulphide ores into oxides on heating strongly in the presence of excess air.It also removes volatile impurities.2ZnS(s)+3O2(g)+Heat→2ZnO(s)+2SO2(g) Calcination Converts carbonate and hydrated ores into oxides on heating strongly in the presence of limited air. It also removes volatile impurities. ZnCO3(s)+heat→ZnO(s)+CO2(g)CaCO3(s)+heat→CaO(s)+CO2(g)Al2O3.2H2O(s)+heat→2Al2O3(s)+2H2O(l)2Fe2O3.3H2O(s)+heat→2Fe2O3(s)+3H2O(l) Reaction of Metals with Water or Steam Aluminium, iron, and zinc are metals that do…

  • Reactivity Series

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    The reactivity series of metals, also known as the activity series, refers to the arrangement of metals in the descending order of their reactivities. The below table illustrates the reactivity of metals from high order to low order. Symbol               Element K Potassium ( Highly Active Metal) Ba Barium…