User:Sisindrisisi/sandbox

"TYPES OF SUBSTANCES""To understand practically about substances do an activity, take two beakers with half filled water and add one or two spoons of sugar or salt in one beaker and sand in another beaker and stir both solutions. observe the differences and note the observations.""Before going to start about the types of substances, let us see what is substance. substance is the material which is definite composition and has specific properties. for example sugar,salt,gold,water,tin,silver,sand, copper,hydrogen,oxygen are the some examples of the substances.""There are two types of substances.""1) Pure substances""2) Mixtures""Now we will see what exactly pure substance and mixtures. basically the substances which are pure known as pure substances, means it has only same kind of particles and has fixed physical and chemical properties. and pure substances can not be separated to any kind of other particles.examples for pure substances are gold,water.""here also we can observe the two types of pure substances.these are elements and compounds. elements are the particles or atoms which are only one kind of pure chemical substance. like gold and hydrogen. two or more elements together with uniform composition will form the compound. for example water ,salt,sugar are the compounds. these compounds contains different elements but composition will be same throughout.""When two or more substances together forms in different ratios and each substance has its own chemical identities are called as mixtures. for example sugar solution, salt solution, soda water, and also soft drinks are mixtures. here also we can see the two types of mixtures. these are homogeneous mixture and heterogeneous mixture.""The mixture which has uniform composition throughout is called as the homogeneous mixture. in other words homogeneous mixtures looks same throughout the solution. when we mix sugar with water and stir the solution, sugar will completely dissolves in water and forms a uniform composition. where when we add sand with water will not form a uniform composition and also sand particles will settle at the bottom of the water will separate the the solution.these kind of mixtures where mixtures which does not have the uniform composition are called heterogeneous mixtures."