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Periodic table part 2

Periodic table    part-2 (E):   Telluric Helix : A three dimensional periodic table given by De-chan-chortois.  This table is also known as tellurix helix.  (F):  Mendeleev's periodic table: Mendeleev's   periodic law - The physical and chemical properties of element are the periodic function of their atomic wt. It is based on atomic weight. 63 element was known noble gases were not discovered. He was the first scientist to classify the elements in a systematic manner that is in horizontal row and in vertical columns. Horizontal rows are called periods and there was 7 periods in Mendeleev periodic table Vertical columns are called groups and there were eight groups in Mendeleev periodic table. Each group of 28 is divided into a and b subgroups a Sub group elements are called Normal elements and B Sub group elements are called transition elements. The metal belonging to the same group exhibit similar properties.  Demerits of Mendeleev's periodic table: Position of hydrogen...
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periodic table part 1

Periodic table  Part.1 (A)   Prouts concept  Is simply asm.com the elements are made up of hydrogen so we can say that  .. Atomic weight of element= n×(Atomic weight.of one hydrogen atom) Where n= no. of hydrogen atom= 123 Drawbacks or limitations: Letter on elements discovered having atomic weight infections like chlorine atomic weight 35.5, Strontium atomic weight 87.5 and proud could not explain why this weights are instructions beasar this is a drawback. (B).   Dobereiner trait rule He made groups of three elements having similar chemical properties  In Dobereiner trait, atomic weight of middle element is equal to the average atomic weight of first and third element. Eg.   Cl               Br.            I          35.5           80.0.         127                  35.5+127/2 =  81.25 (C) Newland law of octaves He arrange the element in increasing order of their atomic mass and observe that properties of every 8th element was similar to the first one like in the case of musical vowe...
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Gravitation

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Gravitation: Newton's law of gravitation  Gravitation and Integral mass.              Gravity.                                                         
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Relative Velocity

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Relative Velocity position time graph of two object with equal to 
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Relative Velocity

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Relative Velocity position time graph of two object with equal to 
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Mass and weight

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Mass and Weight  Mass of a substance is the amount of matter present in it while weight is the force exerted by gravity on an object. The mass of a substance is constant whereas its weight may vary from one place to another due to change in gravity. The mass of a substance can be determined to very accurately in the laboratory by using an analytical balance. The SI unit of mass given as in in figure is kilogram however its fraction gram 1 Kg is equal to 1000 gram is used in Laboratories to the smaller amounts of chemicals used in chemical reactions. Analytical balance Volume:   volume has the units of length cube. So in SI system volume has units of M cube. But again in chemistry Laboratories commerce small volumes are used. Hens, volume is often denoted in centimetre cube or decimeter cube units.   Are common unit litre which is not an SI unit is used for measurement of volume of liquids. 1 litre is equal to 1000 ml coma 1000 centimetre cube is equal to 1 decimeter cube In the laborat...
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Properties of Matter and their measurements

Properties of matter and their measurements The property of matter can be classified into categories physical properties and chemical properties. Physical properties - physical properties are those properties which can be measured or observed without changing the identity or the composition of a substance. Some examples of physical properties are colour, smell, melting point ,boiling point ,density etc.                                Chemical properties- the measurement of chemical properties requires a chemical change to occur. For example chemical properties are characteristic reactions of different substances, these include acidity or basicity, combustibility etc. Many Properties of Matter such as length, area, volume are quantitative in nature full stop any quantitative observation on measurement is represented by a number followed by units in which it is measured. For example length of a room can be represented as 6 metre, here 6 is the number and M denotes metre the unit in which...
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