1 / 7

6.4 States of Matter & Changes of State

6.4 States of Matter & Changes of State. The three states of matter are: solid, liquid, gas. A change of state requires a change in the thermal energy of a substance. 6.4 States of Matter & Changes of State.

helki
Télécharger la présentation

6.4 States of Matter & Changes of State

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. 6.4 States of Matter & Changes of State The three states of matter are: solid, liquid, gas. A change of state requires a change in the thermal energy of a substance.

  2. 6.4 States of Matter & Changes of State The changes in temperature that occur when a substance absorbs & releases thermal energy can be shown in the heating and cooling graphs below:

  3. 6.4 States of Matter & Changes of State Notice the key aspects of each graph: • Temperature changes occur only when one state is present, represented by the angled parts of the graph. • Temperature remains constant during a change of state, represented by the flat parts of the graph. Absorbed or released thermal energy is being transformed into potential energy, rather than kinetic energy. During melting or boiling, thermal energy absorbed by the particles of a substance is needed to break the bonds that hold them together. During condensation or freezing, thermal energy released by the particles allows them to move closer together rand become more organized.

  4. 6.4 Latent Heat Latent Heat (Q) is the total thermal energy absorbed or released by a substance during a change of state; measure in Joules (J). Latent means ‘hidden’ because there is no measurable change in temperature. Latent Heat of Fusion is the amount of thermal energy required to change a solid into a liquid or a liquid into a solid; solid ↔ liquid. Latent Heat of Vaporization is the amount of thermal energy required to change a liquid into a gas or a gas into a liquid; liquid ↔ gas. Specific Latent Heat (L) is the amount of thermal energy required for 1 kg of a substance to change from one state into another; SI units: (J/kg)

  5. 6.4 Specific Latent Heat Specific Latent Heat of Fusion (Lf) is the amount of thermal energy required to melt or freeze 1 kg of a substance to change from one state into another; SI units: (J/kg) Specific Latent Heat of Vaporization (Lv) is the amount of thermal energy required to boil or condense 1 kg of a substance to change from one state into another; SI units: (J/kg) To calculate the latent heat (Q) during a change of state: SI units: Q ⤍ J;m ⤍ kg; Lf and Lv⤍ (J/kg)

  6. 6.4 States of Matter & Changes of State Every substance has a different specific latent heat because every substance is composed of different particles. SP #1,2 p.292-293

  7. 6.4 Homework • Practice # 1-3 p.293 • Questions # 1, 3, 5-8 p.295

More Related