General Chemistry Notes
- Ammonia is manufactured by the Haber Process
- Full Name of TNT, an explosive is Trinitrotoluene
- Trinitrophenol, which is used as an explosive and antiseptic is also known as Picric Acid.
- Nessler’s Reagent is used for the test of Ammonia and Ammonium Salt. It gives brown precipitates
- Nitric Acid ( HNO3) is manufactured by Electric Arc Process.
- The process of Petroleum refining is called as a fractional distillation
- There are various products having different boiling points which are obtained during fractional distillation. At a boiling point of 30 to 70 celcius there is Petroleum Ether which is used as solvent for drycleaning. At a boiling point of 70 to 120 degrees celcius, there is Petrol or gasoline which is used as a motor fuel and general solvent. At a boiling point of 120 to 150 degrees celcius, there is Benzoline which is also a solvent. Then there is Kerosene at 150 to 300 degrees celcius which is used as an illuminant and as a fuel. And Finally above 300 degrees celcius as boiling point, we have Lubricating oil, vasaline and paraffin wax which are used as lubricant, grease and wax.
- Petrol is obtained by a process called cracking. In this process kerosene and crude oil are broken up into low boiling point hydrocarbons such as Octane and Heptane.
- To prevent knocking in petrol engine, an antiknock agent such as Tetraethyl lead is added. Now in lead free oils it is not used as it also harms catalytic converters.
- Iron commonly have three forms, first form which is the crudest form is cast iron containing 2 to 5 percent carbon. Then there is steel which has 0.15 to 1.5% of carbon. Wrought iron is the purest form of iron having 0.12 to 0.25 percent of carbon.
- On exposure to moist air, in the presence of carbon dioxide, iron is converted into brown hydrated iron oxide ( Fe2O3. 10 H2O). This process is called rusting.
- Stainless steel contains 13% chromium.
- Acids are generally sour, turn blue litmus red and generally give hydrogen with metals.
- An acid is a substance which furnishes H+ ion on dissolving with water. It is proton donor and an electon acceptor.
- Bases react with Acids to produce salt and water. They turn red litmus blue. They are also called alkalies eg. NaOH.
- A base is defined as proton acceptor and an electron donor.
- pH is negative logarithm of H ions. pH of neutral solutions is 7. For acidic solutions, pH is between 0 and 7 and for alkaline solutions it is between 7-14.
- Metals occur in nature as chemical compounds called minerals. If these minerals are used as the starting material for extracting the metal, they are called ores.
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