1 / 11

Chapter 18 Solids

Chapter 18 Solids. Crystal Structure The crystalline structure of many solids results from the repeating orderly arrangement of molecules or atoms to form a geometric shape How the atoms or molecules align themselves depends on the type of molecule or atom . Snowflake H 2 O. Na +

varian
Download Presentation

Chapter 18 Solids

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. Chapter 18Solids

  2. Crystal Structure • The crystalline structure of many solids results from the repeating orderly arrangement of molecules or atoms to form a geometric shape • How the atoms or molecules align themselves depends on the type of molecule or atom Snowflake H2O Na+ Cl-

  3. Crystal Structures Made from Carbon: Fullerine Diamond Carbon Nanotube Graphite

  4. Density Density – how tightly material is packed together. Density = mass volume Density is not mass or volume alone. It is a ratio between the amount of mass per unit volume. Water has a density of 1 gram/cm3

  5. Specific Gravity A standard measure of density is specific gravity which is the ratio of the mass (or weight) of a substance to the mass (or weight) of an equal volume of water. Hydrometer – used for measuring the specific gravity of liquids

  6. Practice Questions: • Which has the greater density – 1 kg of water or 10 kg of water? • Neither. They both have the same density • Which has the greater density – 5 kg of lead or 10 kg of aluminum? • Lead • 3. Which has the greater density – 1 g of uranium or the planet earth? • Uranium • 4. The density of gold is 19.3 g/cm3. What is its specific gravity? • 19.3 g/cm3

  7. Elasticity Elasticity is the property of a body by which it experiences a change in shape when a deforming force acts on it, and by which it returns to its original shape when the deforming force is removed. Materials that do not resume their original shape after being distorted are said to be inelastic.

  8. By hanging a weight on a spring, we are applying a force to the spring. It is found that the stretch is directly proportional to the applied force: This relationship between force and stretch of a spring is called Hooke’s Law F ~ x

  9. Elastic Limit Elastic Limit is the distance that a material can be stretch at which point it will not return to its original shape

  10. Practice Questions: • A certain tree brance is found to obey Hooke’s law. When a 20-kg load is hung from the end of it, the branch sags a distance of 10 cm. If instead, a 40-kg load is hung from the same place, by how much will the branch sag? How about if a 60-kg load were hung from the same place? (Assume that none of these loads makes the branch sag beyond its elastic limit. • 20 cm for a 40 kg weight • 30 cm for a 60 kg weight • 2. If a force of 10 N stretches a certain spring 4 cm, how much stretch will occur for an applied force of 15 N? • 6 cm

More Related