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Metals, Non Metals, Acids and Bases

Metals

  • Malleable, Ductile & Good conductor of electricity
  • High melting & boiling points (Except Na & K)
  • Lustrous, Hard (Except Na & K) & Solid at room temp. (Except Hg)
  • Forms cations or positive ions for ex. lithium batteries as used in cell phones

 

Metalloids

  • Have some properties of metal & some of non-metals
  • For ex. Boron, Silicon, Germanium

Metals, Non Metals, Mettaloids

Non Metals

  • Forms anions except NH3+ & H+
  • Iodine is a non-metal but lustrous
  • Diamond – Purest form of carbon, hardest natural substance, good conductor of heat
  • Graphite – Good conductor of electricity (used in electrodes)

 


Acids & Indicator Dyes

Acids

Forms H+ ion in presence of water Reacts with metals to form Hydrogen
Reacts with bases to form salt & water Sour taste, Ph < 7
Citric Acid – Lemon, Orange Acetic Acid – Vinegar
Lactic acid – Sour milk, Curd Tartaric acid – Tamarind, Raw grapes
Oxalic acid – Tomatoes Formic acid – Ant sting, Nettle leaf sting


Acids and bases

Indicators – Dyes which give different colors in acids and bases

Indicator Color in Acid Color in Base Color
Litmus Red Blue Purple
Red Cabbage Red Green Red
Methyl orange Red Yellow Orange
Turmeric Yellow Red Yellow
Phenolphthalein Colorless Pink Colorless

 

Olfactory Indicators – Based on Smell

  • Vanilla – No smell in presence of a base but natural smell in presence of an acid
  • Onion – No smell in presence of a base but natural smell in presence of an acid

 


Type of Reactions

Exothermic Reactions   
  • Heat producing reactions
  • All combustion reactions
Endothermic Reactions
  • Heat absorbing reactions
  • All decomposition reactions
Oxidation Reaction
  • Addition of O2 or removal of H2
  • Rusting of iron– Formation of Feo (aq.) + Fe2O3
Reduction Reaction
  • Removal of O2 or addition of H2
  • For Ex. Vegetable oil → Vanaspati ghee
Rancity foul smell on oxidation of food material prepared in oil or ghee, when left in open for a long time
Matters can neither be created nor destroyed in a chemical reaction i.e. no. of atoms on LHS = no. of atoms on RHS

 


Important Acids and Bases

Nitric Acid
  • Used in the formation of TNT & RDX (Nitroamine, Cyclonite)
Gastric Juice
  • An acidic digestive fluid (containing HCl), secreted by glands in mucus membrane in stomach
  • Formed due to overeating or emotional factors (too much HCl produced)
Antacids
  • Acid inhibitors help to control hyperacidity
  • Examples include Mg(OH)2, CaCO3, NaHCO3 etc. which finally forms CO2 , & comes out as we Belch
Amphoteric Oxides
  • Oxides showing basic as well as acidic nature
  • For ex. Al oxide, Zn oxide
Aqua Regia
  • HNO3 + 3HCl
  • Dissolves all metals even gold & platinum
K, Na & Li
  • Very reactive metals & reacts vigorously with O2 in presence of air
  • Hence are kept under Kerosene oil
CaCO3
  • Used in toothpaste & chewing gum
Sodium 
  • Used for making tetraethyl or tetramethyl lead (Antiknocking agents)
  • Liquid sodium is used as a coolant in nuclear reactors
NH3 +
  • Used as refrigerant
India Yearbook English India Yearbook Hindi Economic Survey 2017

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