Properties-of-Liquid a presentation .pptx

Properties-of-Liquid a presentation .pptx

1. PROPERTIES OF LIQUID

2. VISCOSITY Thickness/resistance to flow of a liquid Inversely correlated to temperature Directly correlated to the strength of intermolecular forces

3. PARTICLES IN LIQUID Particles are not fixed in place Able to flow and take the shape of the container Denser than gas Fixed volume (not compressible )

4. The viscosity of a liquid is a measurement of its thickness or resistance to flow. Water, gasoline, and other liquids that flow freely have a low viscosity . Honey, syrup, motor oil , and other liquids that do not flow freely , have higher viscosities .

5. MISCIBILITY Dissolve : when solid liquid or gas becomes integrated into a host liquid Miscible liquids : dissolve in each other Immiscible liquids : cannot dissolve each other and articles remain separate.

6. Cohesive force - Is the force that attracts molecules of the same substance . Adhesive force - Is the force that binds molecules of different substances together .

7. Surface tension is defined as the energy required to increase the surface area of a liquid, or the force required to increase the length of a liquid surface by a given amount. This property results from the cohesive forces between molecules at the surface of a liquid, and it causes the surface of a liquid to behave like a stretched rubber membrane.

8. If you place one end of a paper towel in spilled wine, the liquid wicks up the paper towel. A similar process occurs in a cloth towel when you use it to dry off after a shower. These are examples of capillary action —when a liquid flows within a porous material due to the attraction of the liquid molecules to the surface of the material and to other liquid molecules.

9. The meniscus curve of a liquid is the upward or downward curve seen at the top of a liquid in a container. The nature of the curve whether upward (convex) or downward (concave) depends on the surface tension the liquid and its adhesion capacity to the wall of the container.

10. A meniscus phenomenon can be attributed to adhesion and is partially influenced by the relatively high surface tension of the fluid. The molecules of the fluid exhibit an affinity towards the molecules present in the wall of the glass beaker .

11. A concave meniscus occurs when the molecules of the liquid are strongly attracted to the container wall rather than to each other. In that case, the liquid appears to ‘stick’ from the edges forming a concave shape .

12. HOW DO INTERMOLECULAR FORCES AND KINETIC ENERGY AFFECT THE MOVEMENT OF PARTICLES IN A LIQUID?

13. WHAT HAPPENS AT A LIQUID’S BOILING POINT?

14. Boiling is the process by which a liquid turns into a vapor when it is heated to its boiling point. The change from a liquid phase to a gaseous phase occurs when the vapor pressure of the liquid is equal to the atmospheric pressure exerted on the liquid. Boiling is a physical change and molecules are not chemically altered during the process .

15. The boiling point is the temperature at which boiling occurs for a specific liquid . F or example: For water, the boiling point is 100ºc at a pressure of 1 atm. The boiling point of a liquid depends on temperature, atmospheric pressure , and the vapor pressure of the liquid .

16. The vapor pressure of a liquid lowers the amount of pressure exerted on the liquid by the atmosphere. As a result, liquids with high vapor pressures have lower boiling points . Vapor pressure can be increased by heating a liquid and causing more molecules to enter the atmosphere. At the point where the vapor pressure is equal to the atmospheric pressure boiling will begin.

17. The temperature of the liquid remains constant during boiling. FOR EXAMPLE, WATER WILL REMAIN AT 100ºc WHILE BOILING.