ELEMENT : AN INTRODUCTION

• Element is a pure substance which contains same kind of atoms ,like H2,N2,P4,S8.if u will observe then you will find 8 atoms are present in case of S8 but all of them are same kind .Hence we can say very evediently here that sulphur is an element.
• Each element has its full name but they also have their nick name .......i.e.there is provision of short abbreviation which is termed as Symbol .
• The concept of symbol is given by Sir J.J.Berzelius.
• We use first letter for symbol of an element; like for Carbon we use "C" as symbol.But if we find there is similarity in first letter of another element,then we use first and another letter which is not similar , like in case of Chlorine we use "Cl" and for Chromium we use "Cr".
• sometime we find we use their Latin name for determination of symbol.
• Like in case of - Tungsten we use "W" as symbol because its Latin name is "Wolfram"
• By this way we adopt "Fe" as symbol for Iron because its Latin name is "Ferrum"
• Like this there are too many examples for bsymbols which are adopted from their Latin name .

KINDS OF MATTER

• we can classify matter in two sub classes -
• A.Pure matter- a. elements b. compounds
  
• B.Mixture - a. homogeneous b. heterogeneous

KILOGRAM

• Anything which is just equivalent to the mass of the piece of platinum and iridium which is located in Paris .
• Mass of one liter of water at 4 degree centigrade temperature is also termed as kilogram.
• S.I. unit of mass is also kilogram .
• One pound is also equals to .453 kg
  

MATTER

"Anything which has certain mass and occupies some space is termed matter "
here mass is considered as quantity of matter .In other word the measurement of inertia is termed as mass.
Weight is also a term which is very close to mass but there is difference ,mass is constant while weight variates.
weight is denoted by w
w=mg
here m=mass
g=acceleration due to gravity
as we know g variates hence w will be considered as variable value.

the S.I. unit of mass is Kilogram .
here S.I. means Systemae International d Unit
Do you know what is Kilogram?