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This lesson explains about the concept of pure substances and also discusses about elements with their examples.

Gargee Vats
Self motivated..hard working ..passionate about teaching and curious to learn new things...

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please include more ticks to learn dates and sequence of events
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very good explanation...
  1. CLASS IX NCERT SCIENCE Chapter 2 Is Matter around us pure


  2. About Me: Gargee Vats Pursing B.tech from G.B.Pant University of agriculture and technology, Uttarakhand Preparing for UPSC CSE. Learning enthusiast. Follow me : https://unacademy.com/user/tyagi.gargee 1996 Please do Like , Share and Recommend.


  3. Matter (Based on constituent particles) Pure Substances Mixtures CompoundsHomogeneous Heterogeneous Mixtures Elements Mixtures


  4. Pure Substances Fixed composition as single kind of particles. Only one kind of atoms or molecules. No impurities. r Cannot be separated into other kinds of matter by physical process Homogenous throughout its mass. Ex- Water, Sulphur.


  5. Pure substances Elements compounds metals metalloids non metals


  6. Elements Robert Boyle first scientist to use the term element. Basic form that cannot be broken down into more simpler forms by physical or chemical methods. Because made up of only one kind of atoms. Ex- hydrogen, carbon , iodine, bromine etc.


  7. CI He SODIUM A nutrient in table salt CARBON Found in charcoal briquettes CHLORINE Used in swimming pools HELIUM Used to inflate balloons Ca Au AI Si SOCA ALUMINUM Used in oda can SILICON Used to build computer chips CALCIUM GOLD A nutrient in dairy products Ancient currency and ornament Examples of Elements


  8. There are 118 elements known at present Out of which 94 elements occur in nature while 24 elements are man-made. Majority elements are solid, 11 are gases and only 2 are liquid i.e. bromine and mercury.


  9. Thank you!!!!