Changes in Matter

• Physical Change

  Substance changes its physical appearance but not its composition.
• Physical Change


  Changes in a substance that do not involve a change in the identity or chemical make-up of the substance.
• All changes in the state of matter are physical change.
• Endothermic


  Heat energy is absorbed.
• Change in enthalpy is (+)

  Endothermic
• Phase changes under Endothermic

  Melting, Evaporation, and Sublimation
• Breaking bonds is also endothermic process.
• Exothermic


  Heat energy is released in the surrounding.
• Change in enthalpy is (-)


  Exothermic
• Phase Changes in Exothermic

  Condensation, freezing, deposition
• Forming bonds is exothermic also process
• Chemical Change


  A substance is transformed into a chemically different substance.
• Chemical Change


  A change in a substance that involves a change in the identity or chemical make-up of the substance.
• Nuclear Fusion


  Two light nuclei combined together to form heavier nuclei.
• Nuclear Fission


  Splitting of a heavy, unstable nucleus into lighter ones.