Changes in Matter

• Physical change is any change in substance form that does not change its chemical makeup.
• Chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another.
• Chemical change occurs when atoms of a substance are rearranged, and the bonds between the atoms are broken or formed.
• Indicators physical change

  • Change in State
  • Physical deformation
  • Changes is temporary or reversible
• Indicators of chemical change

  • Temperature changes
  • Unexpected color changes
  • Light is given off
  • A solid forms if two clear liquids are mixed
  • Bubbles are formed
  • Different smell
  • Energy is released
• Evidence of chemical change  

  • Production of heat and light.
  • Evolution of gas
  • Temperature change
  • Change in intrinsic properties
  • Formation of precipitate
• Photosynthesis is the most important chemical reaction in the biosphere, as it is the prerequisite for all higher life on earth.