1 / 11

States of matter

Melting Vaporization. States of matter. Objectives. Explain :- Melting The Liquid State Vaporisation. What states exist at the point of melting?. At the melting point the solid and liquid phase exist in equilibrium.

teaton
Download Presentation

States of matter

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Melting Vaporization States of matter

  2. Objectives • Explain :- • Melting • The Liquid State • Vaporisation

  3. What states exist at the point of melting?

  4. At the melting point the solid and liquid phase exist in equilibrium. • The melting point of a solid is the temperature range at which it changes state from solid to liquid • http://www.mhhe.com/physsci/chemistry/animations/chang_7e_esp/enm1s3_4.swf Mc Graw Hill

  5. What’s the difference between freezing and melting point

  6. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point • When the "characteristic freezing point" of a substance is determined, in fact the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice", i.e. the melting point • For most substances, melting and freezing points are approximately equal • A pure organic compound usually melts over a range of two degrees or less. • If the melting point of a pure compound is within a degree of the value found a lab handbook it is presumed to be pure.

  7. Impurities and the Melting point • A sample is impure if it has a melting point range that is lower and /or wider than that the literature value. • More impurities increase this effect.

  8. Melting point Apparatus See handout

  9. Changes in the State of Matter • http://hogan.chem.lsu.edu/matter/chap26/animate3/an26_035.mov Louisiana State University • http://mutuslab.cs.uwindsor.ca/schurko/animations/waterphases/status_water.htm Iowa State University

  10. Vaporisation • Vaporization of an element or compound is a phase transition from the liquid phase to gas phase. There are two types of vaporization: evaporation and boiling. • Evaporation is a phase transition from the liquid phase to gas phase that occurs at temperatures below the boiling temperature at a given pressure. Note: evaporation usually occurs on the surface. • Boiling is a phase transition from the liquid phase to gas phase that occurs at or above the temperature the boiling temperature. Note boiling occurs below the surface. • http://www.chm.davidson.edu/ronutt/che115/Phase/Phase.htm

  11. The End

More Related