10/7 & 10/8 - 8th Grade Agenda Learning Objective: Learn about the boiling point & evaporation Collect HW: Reading & Notetaking p.55-56 Pressurized Bell Demonstration Video: Cosmos Textbook Reading p.98-101 Hw: Reading & Notetaking p.57- 58

Daily Reflection Prompt: Why does molecules slow down when temperature goes down?

What are we measuring when we measure temperature? Movement of Molecules Solid Liquid Gas

What is the difference between these patterns? Molecules form Regular Pattern Molecules form Irregular Pattern Crystalline solids Amorphous solids

Solids that is made up of crystals in which particles are arranged in a regular repeating pattern is cr_______ solids ystalline Salts Snow

Am_______ solids are made up of particles that are not arranged in regular pattern orphous Plastics

Crystalline vs Amorphous Solids When a crystalline solid is heated, it melts at a specific temperature Amorphous solid does not melt at a distinct temperature Why?

What are properties of Solid molecules? A solid keeps its own shape. It doesn’t take the shape of a container The particles vibrate back and forth within the solid

What are properties of Liquid molecules? Liquid volume does not change, it takes the shape of whatever container you pour it into. How do particles of liquid differ from the particles of a solid?

What are properties of gas molecules? The particles of gas can be squeezed into a small volume. If allowed to, they will spread out with limit.

The resistance of a liquid to flowing is called vi_______ scosity Which has higher viscosity? Syrup Water

What is surface tension? Surface ten______ is the result of an inward pull among the mole_______ of liquid that brings the molecules on the surface closer together. Surface tension enables the ins______ to walk on the calm surface of a pond. cules ect

What is the temperature where a Solid turns into a Liquid called? Melting Point

What is the temperature where a Liquid turns into a Gas called? Boiling Point

Liquid water changing into water vapor is an example of va__________ porization

When vaporization takes place only on the surface of the liquid the process is called eva__________ poration

When vaporization takes place inside a liquid as well as at the surface, the process is called b_______ oiling

What happens to the Boiling Point when you go to higher elevation? Boiling Point Depends on Air Pressure In the city of Denver (1600 meters above sea level, water boils at 95 degrees Celsius) That is why you have to boil longer at higher elevation.

Co_________ occurs when gas loses enough thermal energy to become a liquid. ndensation Occurs when a gas loses enough thermal energy to become a liquid: i.e. breathing onto a mirror.

limation Sub_________ occurs when the surface particles of a solid gain enough energy to become a gas. When the surface particles of a solid gain enough energy to become a gas without becoming a liquid.

What happens to Volume when Pressure is increased?

What happens to Volume when Pressure is decreased? This is Boyle’s Law

Which cylinder has more pressure Which cylinder has more pressure? What is happening to the volume of the cylinder with more pressure?

What is Boyle’s Law? When the pressure of gas increased, the volume decreases. When pressure decreased, the volume increases